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1. Estimate of Background Baseline and Upper Limit on the Chiral Magnetic Effect in Isobar Collisions at $\sqrt{s_{\text{NN}}}=200$ GeV at the Relativistic Heavy-Ion Collider

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Alpatov, E., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bhosale, S. R., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Broodo, C., Cai, X. Z., Caines, H., Calderón~de~la~Barca~Sánchez, M., Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Gao, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Keane, D., Kechechyan, A., Khanal, A., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kraeva, A. Yu., Kravtsov, P., Kumar, L., Labonte, M. C., Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, D., Li, H-S., Li, H., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Lin, Y., Liu, C., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Luo, J., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Manikandhan, R., Margetis, S., Matis, H. S., McNamara, G., Mezhanska, O., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, M., Nedorezov, E., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pal, S., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Povarov, A., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Racz, C., Radhakrishnan, S. K., Rana, A., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schaefer, B. C., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A. C., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Trentalange, S., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Tyler, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, J., Wang, K., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: For the search of the chiral magnetic effect (CME), STAR previously presented the results from isobar collisions (${^{96}_{44}\text{Ru}}+{^{96}_{44}\text{Ru}}$, ${^{96}_{40}\text{Zr}}+{^{96}_{40}\text{Zr}}$) obtained through a blind analysis. The ratio of results in Ru+Ru to Zr+Zr collisions for the CME-sensitive charge-dependent azimuthal correlator ($\Delta\gamma$), normalized by elliptic anisotropy ($v_{2}$), was observed to be close to but systematically larger than the inverse multiplicity ratio. The background baseline for the isobar ratio, $Y = \frac{(\Delta\gamma/v_{2})^{\text{Ru}}}{(\Delta\gamma/v_{2})^{\text{Zr}}}$, is naively expected to be $\frac{(1/N)^{\text{Ru}}}{(1/N)^{\text{Zr}}}$; however, genuine two- and three-particle correlations are expected to alter it. We estimate the contributions to $Y$ from those correlations, utilizing both the isobar data and HIJING simulations. After including those contributions, we arrive at a final background baseline for $Y$, which is consistent with the isobar data. We extract an upper limit for the CME fraction in the $\Delta\gamma$ measurement of approximately $10\%$ at a $95\%$ confidence level on in isobar collisions at $\sqrt{s_{\text{NN}}} = 200$ GeV, with an expected $15\%$ difference in their squared magnetic fields., Comment: 19 pages, 14 figures
Published: 2023
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2. Upper Limit on the Chiral Magnetic Effect in Isobar Collisions at the Relativistic Heavy-Ion Collider

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Alpatov, E., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bhosale, S. R., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Broodo, C., Cai, X. Z., Caines, H., Calderón~de~la~Barca~Sánchez, M., Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Gao, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Keane, D., Kechechyan, A., Khanal, A., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kraeva, A. Yu., Kravtsov, P., Kumar, L., Labonte, M. C., Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, D., Li, H-S., Li, H., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Lin, Y., Liu, C., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Luo, J., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Manikandhan, R., Margetis, S., Matis, H. S., McNamara, G., Mezhanska, O., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, M., Nedorezov, E., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pal, S., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Povarov, A., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Racz, C., Radhakrishnan, S. K., Rana, A., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schaefer, B. C., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A. C., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Trentalange, S., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Tyler, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, J., Wang, K., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The chiral magnetic effect (CME) is a phenomenon that arises from the QCD anomaly in the presence of an external magnetic field. The experimental search for its evidence has been one of the key goals of the physics program of the Relativistic Heavy-Ion Collider. The STAR collaboration has previously presented the results of a blind analysis of isobar collisions (${^{96}_{44}\text{Ru}}+{^{96}_{44}\text{Ru}}$, ${^{96}_{40}\text{Zr}}+{^{96}_{40}\text{Zr}}$) in the search for the CME. The isobar ratio ($Y$) of CME-sensitive observable, charge separation scaled by elliptic anisotropy, is close to but systematically larger than the inverse multiplicity ratio, the naive background baseline. This indicates the potential existence of a CME signal and the presence of remaining nonflow background due to two- and three-particle correlations, which are different between the isobars. In this post-blind analysis, we estimate the contributions from those nonflow correlations as a background baseline to $Y$, utilizing the isobar data as well as Heavy Ion Jet Interaction Generator simulations. This baseline is found consistent with the isobar ratio measurement, and an upper limit of 10% at 95% confidence level is extracted for the CME fraction in the charge separation measurement in isobar collisions at $\sqrt{s_{\rm NN}}=200$ GeV., Comment: 8 pages, 4 figures
Published: 2023
Full Text: View/download PDF

3. Event-by-event correlations between $\Lambda$ ($\bar{\Lambda}$) hyperon global polarization and handedness with charged hadron azimuthal separation in Au+Au collisions at $\sqrt{s_{\text{NN}}} = 27 \text{ GeV}$ from STAR

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, M., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Tyler, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Global polarizations ($P$) of $\Lambda$ ($\bar{\Lambda}$) hyperons have been observed in non-central heavy-ion collisions. The strong magnetic field primarily created by the spectator protons in such collisions would split the $\Lambda$ and $\bar{\Lambda}$ global polarizations ($\Delta P = P_{\Lambda} - P_{\bar{\Lambda}} < 0$). Additionally, quantum chromodynamics (QCD) predicts topological charge fluctuations in vacuum, resulting in a chirality imbalance or parity violation in a local domain. This would give rise to an imbalance ($\Delta n = \frac{N_{\text{L}} - N_{\text{R}}}{\langle N_{\text{L}} + N_{\text{R}} \rangle} \neq 0$) between left- and right-handed $\Lambda$ ($\bar{\Lambda}$) as well as a charge separation along the magnetic field, referred to as the chiral magnetic effect (CME). This charge separation can be characterized by the parity-even azimuthal correlator ($\Delta\gamma$) and parity-odd azimuthal harmonic observable ($\Delta a_{1}$). Measurements of $\Delta P$, $\Delta\gamma$, and $\Delta a_{1}$ have not led to definitive conclusions concerning the CME or the magnetic field, and $\Delta n$ has not been measured previously. Correlations among these observables may reveal new insights. This paper reports measurements of correlation between $\Delta n$ and $\Delta a_{1}$, which is sensitive to chirality fluctuations, and correlation between $\Delta P$ and $\Delta\gamma$ sensitive to magnetic field in Au+Au collisions at 27 GeV. For both measurements, no correlations have been observed beyond statistical fluctuations., Comment: 10 pages, 10 figures; paper from the STAR Collaboration
Published: 2023
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4. Observation of the electromagnetic field effect via charge-dependent directed flow in heavy-ion collisions at the Relativistic Heavy Ion Collider

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Alpatov, E., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bhosale, S. R., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Dash, A. P., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Gao, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Keane, D., Kechechyan, A., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kraeva, A. Yu., Kravtsov, P., Kumar, L., Labonte, M. C., Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, H-S., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Lin, Y., Liu, C., Liu, F., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, M., Nedorezov, E., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Povarov, A., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Rana, A., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schaefer, B. C., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A. C., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Trentalange, S., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tsang, C. Y., Tu, Z., Tyler, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, J., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The deconfined quark-gluon plasma (QGP) created in relativistic heavy-ion collisions enables the exploration of the fundamental properties of matter under extreme conditions. Non-central collisions can produce strong magnetic fields on the order of $10^{18}$ Gauss, which offers a probe into the electrical conductivity of the QGP. In particular, quarks and anti-quarks carry opposite charges and receive contrary electromagnetic forces that alter their momenta. This phenomenon can be manifested in the collective motion of final-state particles, specifically in the rapidity-odd directed flow, denoted as $v_1(\mathsf{y})$. Here we present the charge-dependent measurements of $dv_1/d\mathsf{y}$ near midrapidities for $\pi^{\pm}$, $K^{\pm}$, and $p(\bar{p})$ in Au+Au and isobar ($_{44}^{96}$Ru+$_{44}^{96}$Ru and $_{40}^{96}$Zr+$_{40}^{96}$Zr) collisions at $\sqrt{s_{\rm NN}}=$ 200 GeV, and in Au+Au collisions at 27 GeV, recorded by the STAR detector at the Relativistic Heavy Ion Collider. The combined dependence of the $v_1$ signal on collision system, particle species, and collision centrality can be qualitatively and semi-quantitatively understood as several effects on constituent quarks. While the results in central events can be explained by the $u$ and $d$ quarks transported from initial-state nuclei, those in peripheral events reveal the impacts of the electromagnetic field on the QGP. Our data put valuable constraints on the electrical conductivity of the QGP in theoretical calculations.
Published: 2023

5. Hyperon polarization along the beam direction relative to the second and third harmonic event planes in isobar collisions at $\sqrt{s_{NN}}$ = 200 GeV

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Gao, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, M., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Tyler, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, J., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: The polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at $\sqrt{s_{NN}}$ = 200 GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild $p_T$ dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagree with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and $p_T$ dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy., Comment: 6 pages, 5 figures, Published in Physical Review Letters
Published: 2023
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6. Observation of Directed Flow of Hypernuclei $^3_{\Lambda}$H and $^4_{\Lambda}$H in $\sqrt{s_{\rm NN}}$ = 3 GeV Au+Au Collisions at RHIC

Author: STAR Collaboration, Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, Md., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We report here the first observation of directed flow ($v_1$) of the hypernuclei $^3_{\Lambda}$H and $^4_{\Lambda}$H in mid-central Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165 $\times$ 10$^{6}$ events in 5%-40% centrality, about 8400 $^3_{\Lambda}$H and 5200 $^4_{\Lambda}$H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity $v_1$ slopes of $^3_{\Lambda}$H and $^4_{\Lambda}$H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in such collisions., Comment: 5pages, 4 figures. Supplemental material: 6 pages, 5 figures
Published: 2022
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7. Beam energy dependence of the linear and mode-coupled flow harmonics in Au+Au collisions

Author: STAR Collaboration, Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kincses, D., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mooney, I., Morozov, D. A., Mudrokh, A., Mukherjee, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, Md., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: The linear and mode-coupled contributions to higher-order anisotropic flow are presented for Au+Au collisions at $\sqrt{s_{\mathrm{NN}}}$ = 27, 39, 54.4, and 200 GeV and compared to similar measurements for Pb+Pb collisions at the Large Hadron Collider (LHC). The coefficients and the flow harmonics' correlations, which characterize the linear and mode-coupled response to the lower-order anisotropies, indicate a beam energy dependence consistent with an influence from the specific shear viscosity ($\eta/s$). In contrast, the dimensionless coefficients, mode-coupled response coefficients, and normalized symmetric cumulants are approximately beam-energy independent, consistent with a significant role from initial-state effects. These measurements could provide unique supplemental constraints to (i) distinguish between different initial-state models and (ii) delineate the temperature ($T$) and baryon chemical potential ($\mu_{B}$) dependence of the specific shear viscosity $\frac{\eta}{s} (T, \mu_B)$., Comment: 11 pages, 4 figures
Published: 2022
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8. Measurements of the elliptic and triangular azimuthal anisotropies in central $^{3}$He+Au, $d$+Au and $p$+Au collisions at $\mbox{$\sqrt{s_{\mathrm{NN}}}$}$ = 200 GeV

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, G., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, Md., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, W., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: The elliptic ($v_2$) and triangular ($v_3$) azimuthal anisotropy coefficients in central $^{3}$He+Au, $d$+Au, and $p$+Au collisions at $\mbox{$\sqrt{s_{\mathrm{NN}}}$}$ = 200 GeV are measured as a function of transverse momentum ($p_{\mathrm{T}}$) at mid-rapidity ($|\eta|<$0.9), via the azimuthal angular correlation between two particles both at $|\eta|<$0.9. While the $v_2(p_{\mathrm{T}})$ values depend on the colliding systems, the $v_3(p_{\mathrm{T}})$ values are system-independent within the uncertainties, suggesting an influence on eccentricity from sub-nucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems., Comment: 5 pages, 4 figures
Published: 2022

9. Beam Energy Dependence of Triton Production and Yield Ratio ($\mathrm{N}_t \times \mathrm{N}_p/\mathrm{N}_d^2$) in Au+Au Collisions at RHIC

Author: STAR Collaboration, Abdulhamid, M. I., Aboona, B. E., Adam, J., Adams, J. R., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aslam, S., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Calderón~de~la~Barca~Sánchez, M., Cebra, D., Ceska, J., Chakaberia, I., Chan, B. K., Chang, Z., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, Z., Cheng, J., Cheng, Y., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Dale-Gau, G., Das, A., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Flor, F. A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison-Smith, H., He, W., He, X. H., He, Y., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jalotra, A., Jena, C., Ji, Y., Jia, J., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Lacey, R., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Liu, C., Liu, F., Liu, H., Liu, L., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Lomicky, O., Longacre, R. S., Loyd, E. M., Lu, T., Lukow, N. S., Luo, X. F., Luong, V. B., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Mi, K., Minaev, N. G., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mudrokh, A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, Md., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Pani, T., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Posik, M., Protzman, T., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Robertson, C. W., Rogachevsky, O. V., Aguilar, M. A. Rosales, Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, T., Sharma, M., Sharma, N., Sharma, R., Sharma, S. R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Si, F., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Su, Y., Sun, C., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tamis, A., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M. V., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tsai, O. D., Tsang, C. Y., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wilks, G., Wissink, S. W., Wu, J., Wu, X., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, N., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, S., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, High Energy Physics - Theory, Nuclear Theory
Abstract: We report the triton ($t$) production in mid-rapidity ($|y| <$ 0.5) Au+Au collisions at $\sqrt{s_\mathrm{NN}}$= 7.7--200 GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider (RHIC). The nuclear compound yield ratio ($\mathrm{N}_t \times \mathrm{N}_p/\mathrm{N}_d^2$), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity ($dN_{ch}/d\eta$) and follows a scaling behavior. The $dN_{ch}/d\eta$ dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0\%-10\% most central collisions at 19.6 and 27 GeV, with a significance of 2.3$\sigma$ and 3.4$\sigma$, respectively, giving a combined significance of 4.1$\sigma$. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller $p_{T}$ acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed., Comment: 6 pages, 4 figures, Supplemental Material: http://link.aps.org/supplemental/10.1103/PhysRevLett.130.202301
Published: 2022
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10. Pion, kaon, and (anti-)proton production in U+U Collisions at $\sqrt{s_{NN}}$ = 193 GeV measured with the STAR detector

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Atchison, J., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Bhagat, P., Bhasin, A., Bhatta, S., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chan, B. K., Chang, Z., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Hamed, A., Han, Y., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Hoffman, E., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Ji, Y., Jia, J., Jiang, K., Jin, C., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kimelman, B., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A. A., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Li, Z., Liang, X., Liang, Y., Lin, T., Lin, Y., Liu, F., Liu, H., Liu, T., Liu, X., Liu, Y., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Matis, H. S., Mazer, J. A., McNamara, G., Minaev, N. G., Mishra, D., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Nagy, M. I., Nain, A. S., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Perkins, C., Pokhrel, B. R., Porter, J., Posik, M., Pruthi, N. K., Putschke, J., Qin, Z., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Ritter, H. G., Rogachevsky, O. V., Romero, J. L., Roy, D., Chowdhury, P. Roy, Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sato, S., Schmidke, W. B., Schmitz, N., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shen, K., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Söhngen, Y., Solyst, W., Song, Y., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Sun, C., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tsang, C. Y., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vasiliev, A. N., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wielanek, D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yan, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, J., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: We present the first measurements of transverse momentum spectra of $\pi^{\pm}$, $K^{\pm}$, $p(\bar{p})$ at midrapidity ($|y| < 0.1$) in U+U collisions at $\sqrt{s_{NN}}$ = 193 GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The centrality dependence of particle yields, average transverse momenta, particle ratios and kinetic freeze-out parameters are discussed. The results are compared with the published results from Au+Au collisions at $\sqrt{s_{NN}} =$ 200 GeV in STAR. The results are also compared to those from A Multi Phase Transport (AMPT) model., Comment: 17 pages, 14 figures and 7 tables; Replaced with the updated version published in Physical Review C
Published: 2022
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11. Two-particle correlations on transverse rapidity in Au+Au collisions at $\sqrt{s_{\rm NN}}=200$ GeV at STAR

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bhattarai, P., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oldag, E. W., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Two-particle correlation measurements projected onto two-dimensional, transverse rapidity coordinates ($y_{T1},y_{T2}$), allow access to dynamical properties of the QCD medium produced in relativistic heavy-ion collisions that angular correlation measurements are not sensitive to. We report non-identified charged-particle correlations for Au + Au minimum-bias collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV taken by the STAR experiment at the Relativistic Heavy-Ion Collider (RHIC). Correlations are presented as 2D functions of transverse rapidity for like-sign, unlike-sign and all charged-particle pairs, as well as for particle pairs whose relative azimuthal angles lie on the near-side, the away-side, or at all relative azimuth. The correlations are constructed using charged particles with transverse momentum $p_T \geq 0.15$ GeV/$c$, pseudorapidity from $-$1 to 1, and azimuthal angles from $-\pi$ to $\pi$. The significant correlation structures that are observed evolve smoothly with collision centrality. The major correlation features include a saddle shape plus a broad peak with maximum near $y_T \approx 3$, corresponding to $p_T \approx$ 1.5 GeV/$c$. The broad peak is observed in both like- and unlike-sign charge combinations and in near- and away-side relative azimuthal angles. The all-charge, all-azimuth correlation measurements are compared with the theoretical predictions of {\sc hijing} and {\sc epos}. The results indicate that the correlations for peripheral to mid-central collisions can be approximately described as a superposition of nucleon + nucleon collisions with minimal effects from the QCD medium. Strong medium effects are indicated in mid- to most-central collisions.
Published: 2022

12. Pattern of Global Spin Alignment of $\phi$ and $K^{*0}$ mesons in Heavy-Ion Collisions

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Phenomenology, Nuclear Experiment
Abstract: Notwithstanding decades of progress since Yukawa first developed a description of the force between nucleons in terms of meson exchange, a full understanding of the strong interaction remains a major challenge in modern science. One remaining difficulty arises from the non-perturbative nature of the strong force, which leads to the phenomenon of quark confinement at distances on the order of the size of the proton. Here we show that in relativistic heavy-ion collisions, where quarks and gluons are set free over an extended volume, two species of produced vector (spin-1) mesons, namely $\phi$ and $K^{*0}$, emerge with a surprising pattern of global spin alignment. In particular, the global spin alignment for $\phi$ is unexpectedly large, while that for $K^{*0}$ is consistent with zero. The observed spin-alignment pattern and magnitude for the $\phi$ cannot be explained by conventional mechanisms, while a model with a connection to strong force fields, i.e. an effective proxy description within the Standard Model and Quantum Chromodynamics, accommodates the current data. This connection, if fully established, will open a potential new avenue for studying the behaviour of strong force fields.
Published: 2022
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13. Tomography of Ultra-relativistic Nuclei with Polarized Photon-gluon Collisions

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Klein, S. R., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, Nuclear Theory, Quantum Physics
Abstract: A linearly polarized photon can be quantized from the Lorentz-boosted electromagnetic field of a nucleus traveling at ultra-relativistic speed. When two relativistic heavy nuclei pass one another at a distance of a few nuclear radii, the photon from one nucleus may interact through a virtual quark-antiquark pair with gluons from the other nucleus forming a short-lived vector meson (e.g. ${\rho^0}$). In this experiment, the polarization was utilized in diffractive photoproduction to observe a unique spin interference pattern in the angular distribution of ${\rho^0\rightarrow\pi^+\pi^-}$ decays. The observed interference is a result of an overlap of two wave functions at a distance an order of magnitude larger than the ${\rho^0}$ travel distance within its lifetime. The strong-interaction nuclear radii were extracted from these diffractive interactions, and found to be $6.53\pm 0.06$ fm ($^{197} {\rm Au }$) and $7.29\pm 0.08$ fm ($^{238} {\rm U}$), larger than the nuclear charge radii. The observable is demonstrated to be sensitive to the nuclear geometry and quantum interference of non-identical particles.
Published: 2022
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14. Centrality and transverse momentum dependence of higher-order flow harmonics of identified hadrons in Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We present high-precision measurements of elliptic, triangular, and quadrangular flow $v_{2}$, $v_{3}$, and $v_{4}$, respectively, at midrapidity ($|\eta|<1.0$) for identified hadrons $\pi$, $p$, $K$, $\varphi$, $K_s$, $\Lambda$ as a function of centrality and transverse momentum in Au+Au collisions at the center-of-mass energy $\sqrt{s_{\rm NN}}=$ 200 GeV. We observe similar $v_{n}$ trends between light and strange mesons which indicates that the heavier strange quarks flow as strongly as the lighter up and down quarks. The number-of-constituent-quark scaling for $v_{2}$, $v_{3}$, and $v_{4}$ is found to hold within statistical uncertainty for 0-10$\%$, 10-40$\%$ and 40-80$\%$ collision centrality intervals. The results are compared to several viscous hydrodynamic calculations with varying initial conditions, and could serve as an additional constraint to the development of hydrodynamic models., Comment: 15 pages, 11 figures, submitted for publication
Published: 2022

15. Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Elliptic flow measurements from two-, four- and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at $\sqrt{s_{\rm NN}}$= 193 GeV, Cu+Au at $\sqrt{s_{\rm NN}}$= 200 GeV and Au+Au spanning the range $\sqrt{s_{\rm NN}}$= 11.5 - 200 GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and T$\mathrel{\protect\raisebox{-2.1pt}{R}}$ENTo model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied., Comment: 9 pages, 4 figures
Published: 2022
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16. Light Nuclei Collectivity from $\sqrt{s_{\rm NN}}$ = 3 GeV Au+Au Collisions at RHIC

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L. S., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: In high-energy heavy-ion collisions, partonic collectivity is evidenced by the constituent quark number scaling of elliptic flow anisotropy for identified hadrons. A breaking of this scaling and dominance of baryonic interactions is found for identified hadron collective flow measurements in $\sqrt{s_{\rm NN}}$ = 3 GeV Au+Au collisions. In this paper, we report measurements of the first- and second-order azimuthal anisotropic parameters, $v_1$ and $v_2$, of light nuclei ($d$, $t$, $^{3}$He, $^{4}$He) produced in $\sqrt{s_{\rm NN}}$ = 3 GeV Au+Au collisions at the STAR experiment. An atomic mass number scaling is found in the measured $v_1$ slopes of light nuclei at mid-rapidity. For the measured $v_2$ magnitude, a strong rapidity dependence is observed. Unlike $v_2$ at higher collision energies, the $v_2$ values at mid-rapidity for all light nuclei are negative and no scaling is observed with the atomic mass number. Calculations by the Jet AA Microscopic Transport Model (JAM), with baryonic mean-field plus nucleon coalescence, are in good agreement with our observations, implying baryonic interactions dominate the collective dynamics in 3 GeV Au+Au collisions at RHIC.
Published: 2021
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17. Measurements of Proton High Order Cumulants in 3 GeV Au+Au Collisions and Implications for the QCD Critical Point

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at 3.0 GeV, measured by the STAR experiment in the kinematic acceptance of rapidity ($y$) and transverse momentum ($p_{\rm T}$) within $-0.5 < y<0$ and $0.4 < p_{\rm T} <2.0 $ GeV/$c$. In the most central 0--5\% collisions, a proton cumulant ratio is measured to be $C_4/C_2=-0.85 \pm 0.09 ~(\rm stat.) \pm 0.82 ~(\rm syst.)$, which is less than unity, the Poisson baseline. The hadronic transport UrQMD model reproduces our $C_4/C_2$ in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in $C_4/C_2$ is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3\,GeV.
Published: 2021
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18. Evidence for Nonlinear Gluon Effects in QCD and their $A$ Dependence at STAR

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Theory, Nuclear Theory
Abstract: The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-$\pi^0$s produced at forward pseudorapidities ($2.6<\eta<4.0$) in $p$+$p$, $p+$Al, and $p+$Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back $\pi^0$ pairs in $p+$Al and $p+$Au collisions compared to the $p$+$p$ data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in $p+$Au relative to $p+$Al collisions exhibits a dependence of the saturation scale, $Q_s^2$, on the mass number, $A$. A linear scaling of the suppression with $A^{1/3}$ is observed with a slope of $-0.09$ $\pm$ $0.01$., Comment: 7 pages,3 figures, 1 supplemental material
Published: 2021
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19. Longitudinal double-spin asymmetry for inclusive jet and dijet production in polarized proton collisions at $\sqrt{s}=510$ GeV

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Aitbaev, A., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Feng, C. J., Feng, Y., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, C., Hu, Q., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Isshiki, M., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Korobitsin, A., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lu, T., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Manukhov, S. L., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Okubo, K., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Paul, A., Pawlik, B., Pawlowska, D., Perkins, C., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Samigullin, E., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sharma, R., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Singh, J., Singha, S., Sinha, P., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, F., Zhao, J., Zhao, M., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report measurements of the longitudinal double-spin asymmetry, $A_{LL}$, for inclusive jet and dijet production in polarized proton-proton collisions at midrapidity and center-of-mass energy $\sqrt{s}$ = 510 GeV, using the high luminosity data sample collected by the STAR experiment in 2013. These measurements complement and improve the precision of previous STAR measurements at the same center-of-mass energy that probe the polarized gluon distribution function at partonic momentum fraction 0.015 $\lesssim x \lesssim$ 0.25. The dijet asymmetries are separated into four jet-pair topologies, which provide further constraints on the $x$ dependence of the polarized gluon distribution function. These measurements are in agreement with previous STAR measurements and with predictions from current next-to-leading order global analyses. They provide more precise data at low dijet invariant mass that will better constraint the shape of the polarized gluon distribution function of the proton.
Published: 2021

20. Measurement of cold nuclear matter effects for inclusive $J/\psi$ in $p$+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200 GeV

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Measurement by the STAR experiment at RHIC of the cold nuclear matter (CNM) effects experienced by inclusive $J/\psi$ at mid-rapidity in 0-100\% $p$+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200 GeV is presented. Such effects are quantified utilizing the nuclear modification factor, $R_{p\mathrm{Au}}$, obtained by taking a ratio of $J/\psi$ yield in $p$+Au collisions to that in $p$+$p$ collisions scaled by the number of binary nucleon-nucleon collisions. The differential $J/\psi$ yield in both $p$+$p$ and $p$+Au collisions is measured through the dimuon decay channel, taking advantage of the trigger capability provided by the Muon Telescope Detector in the RHIC 2015 run. Consequently, the $J/\psi$ $R_{p\mathrm{Au}}$ is derived within the transverse momentum ($p_{\mathrm{T}}$) range of 0 to 10 GeV/$c$. A suppression of approximately 30% is observed for $p_{\mathrm{T}}<2$ GeV/$c$, while $J/\psi$ $R_{p\mathrm{Au}}$ becomes compatible with unity for $p_{\mathrm{T}}$ greater than 3 GeV/$c$, indicating the $J/\psi$ yield is minimally affected by the CNM effects at high $p_{\mathrm{T}}$. Comparison to a similar measurement from 0-20% central Au+Au collisions reveals that the observed strong $J/\psi$ suppression above 3 Gev/$c$ is mostly due to the hot medium effects, providing strong evidence for the formation of the quark-gluon plasma in these collisions. Several model calculations show qualitative agreement with the measured $J/\psi$ $R_{p\mathrm{Au}}$, while their agreement with the $J/\psi$ yields in $p$+$p$ and $p$+Au collisions is worse., Comment: 5 figures
Published: 2021
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21. Measurements of ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$ Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We report precision measurements of hypernuclei ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$ lifetimes obtained from Au+Au collisions at \snn = 3.0\,GeV and 7.2\,GeV collected by the STAR experiment at RHIC, and the first measurement of ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$ mid-rapidity yields in Au+Au collisions at \snn = 3.0\,GeV. ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be $221\pm15(\rm stat.)\pm19(\rm syst.)$\,ps for ${}^3_\Lambda \rm{H}$ and $218\pm6(\rm stat.)\pm13(\rm syst.)$\,ps for ${}^4_\Lambda \rm{H}$. The $p_T$-integrated yields of ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$ are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of ${}^4_\Lambda \rm{H}$ is different for 0--10\% and 10--50\% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the ${}^3_\Lambda \rm{H}$ yield well, while underestimating the ${}^4_\Lambda \rm{H}$ yield. Transport models, combining baryonic mean-field and coalescence (JAM) or utilizing dynamical cluster formation via baryonic interactions (PHQMD) for light nuclei and hypernuclei production, approximately describe the measured ${}^3_\Lambda \rm{H}$ and ${}^4_\Lambda \rm{H}$ yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei., Comment: 8 pages, 4 captioned figures
Published: 2021
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22. Measurement of inclusive electrons from open heavy-flavor hadron decays in $p$+$p$ collisions at $\sqrt{s} = 200$ GeV with the STAR detector

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., arwal, M. M. Agg, Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., n, I. G. Bordyuzhi, Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., h, T. G. Dedovic, Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., lop, J. C. Dun, Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N ., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W ., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J ., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., acey, R. L, Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y ., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., e, W. J. Llop, Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., sim, Md. Na, Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., k, B. Pawli, Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., ova, V. Prozor, Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., ter, H. G. Rit, Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., han, P. V. Shanmuganat, Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., rida, D. N. Svi, Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., loshin, S. A. Vo, Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., n, H. Wiema, Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., g, S. Yan, Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We report a new measurement of the production cross section for inclusive electrons from open heavy-flavor hadron decays as a function of transverse momentum ($p_{\rm T}$) at mid-rapidity ($|y|<$ 0.7) in $p$+$p$ collisions at $\sqrt{s} = 200$ GeV. The result is presented for 2.5 $
Published: 2021
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23. Differential measurements of jet substructure and partonic energy loss in Au$+$Au collisions at $\sqrt{s_{\rm{NN}}} =200$ GeV

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The STAR collaboration presents jet substructure measurements related to both the momentum fraction and the opening angle within jets in \pp and \AuAu collisions at \sqrtsn $= 200$ GeV. The substructure observables include SoftDrop groomed momentum fraction (\zg), groomed jet radius (\rg), and subjet momentum fraction (\zsj) and opening angle (\tsj). The latter observable is introduced for the first time. Fully corrected subjet measurements are presented for \pp collisions and are compared to leading order Monte Carlo models. The subjet \tsj~distributions reflect the jets leading opening angle and are utilized as a proxy for the resolution scale of the medium in \AuAu collisions. We compare data from \AuAu collisions to those from \pp which are embedded in minimum-bias \AuAu events in order to include the effects of detector smearing and the heavy-ion collision underlying event. The subjet observables are shown to be more robust to the background than \zg~and \rg. We observe no significant modifications of the subjet observables within the two highest-energy, back-to-back jets, resulting in a distribution of opening angles and the splittings that are vacuum-like. We also report measurements of the differential di-jet momentum imbalance ($A_{\rm{J}}$) for jets of varying \tsj. We find no qualitative differences in energy loss signatures for varying angular scales in the range $0.1 < $ \tsj $ < 0.3$, leading to the possible interpretation that energy loss in this population of high momentum di-jet pairs, is due to soft medium-induced gluon radiation from a single color-charge as it traverses the medium., Comment: 17 pages, 11 figures, 1 Appendix. Published version
Published: 2021
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24. Probing the gluonic structure of the deuteron with $J/\psi$ photoproduction in d+Au ultra-peripheral collisions

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Lewis, N., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Song, Y., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, X., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, G., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultra-peripheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of $J/\psi$ photoproduction off the deuteron in UPCs at the center-of-mass energy $\sqrt{s_{_{\rm NN}}}=200~\rm GeV$ in d$+$Au collisions. The differential cross section as a function of momentum transfer $-t$ is measured. In addition, data with a neutron tagged in the deuteron-going Zero-Degree Calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the Color Glass Condensate saturation model and the gluon shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup, which provides insights into the nuclear gluonic structure., Comment: Final published version Phys. Rev. Lett. 128, 122303
Published: 2021
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25. Search for the Chiral Magnetic Effect with Isobar Collisions at $\sqrt{s_{NN}}$ = 200 GeV by the STAR Collaboration at RHIC

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, A. K., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D. Y., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: The chiral magnetic effect (CME) is predicted to occur as a consequence of a local violation of $\cal P$ and $\cal CP$ symmetries of the strong interaction amidst a strong electro-magnetic field generated in relativistic heavy-ion collisions. Experimental manifestation of the CME involves a separation of positively and negatively charged hadrons along the direction of the magnetic field. Previous measurements of the CME-sensitive charge-separation observables remain inconclusive because of large background contributions. In order to better control the influence of signal and backgrounds, the STAR Collaboration performed a blind analysis of a large data sample of approximately 3.8 billion isobar collisions of $^{96}_{44}$Ru+$^{96}_{44}$Ru and $^{96}_{40}$Zr+$^{96}_{40}$Zr at $\sqrt{s_{\rm NN}}=200$ GeV. Prior to the blind analysis, the CME signatures are predefined as a significant excess of the CME-sensitive observables in Ru+Ru collisions over those in Zr+Zr collisions, owing to a larger magnetic field in the former. A precision down to 0.4% is achieved, as anticipated, in the relative magnitudes of the pertinent observables between the two isobar systems. Observed differences in the multiplicity and flow harmonics at the matching centrality indicate that the magnitude of the CME background is different between the two species. No CME signature that satisfies the predefined criteria has been observed in isobar collisions in this blind analysis., Comment: 43 pages, 27 figures
Published: 2021

26. Probing Strangeness Canonical Ensemble with $K^{-}$, $\phi(1020)$ and $\Xi^{-}$ Production in Au+Au Collisions at ${\sqrt{s_{\rm NN}} = \rm{3\,GeV}}$

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhou, Y., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We report the first multi-differential measurements of strange hadrons of $K^{-}$, $\phi$ and $\Xi^{-}$ yields as well as the ratios of $\phi/K^-$ and $\phi/\Xi^-$ in Au+Au collisions at ${\sqrt{s_{\rm NN}} = \rm{3\,GeV}}$ with the STAR experiment fixed target configuration at RHIC. The $\phi$ mesons and $\Xi^{-}$ hyperons are measured through hadronic decay channels, $\phi\rightarrow K^+K^-$ and $\Xi^-\rightarrow \Lambda\pi^-$. Collision centrality and rapidity dependence of the transverse momentum spectra for these strange hadrons are presented. The $4\pi$ yields and ratios are compared to thermal model and hadronic transport model predictions. At this collision energy, thermal model with grand canonical ensemble (GCE) under-predicts the $\phi/K^-$ and $\phi/\Xi^-$ ratios while the result of canonical ensemble (CE) calculations reproduce $\phi/K^-$, with the correlation length $r_c \sim 2.7$\,fm, and $\phi/\Xi^-$, $r_c \sim 4.2$\,fm, for the 0-10\% central collisions. Hadronic transport models including high mass resonance decays could also describe the ratios. While thermal calculations with GCE work well for strangeness production in high energy collisions, the change to CE at $\rm{3\,GeV}$ implies a rather different medium property at high baryon density., Comment: 9 pages, 5 figures, 2 tables
Published: 2021
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27. Disappearance of partonic collectivity in $\sqrt{s_{NN}}$ = 3 GeV Au+Au collisions at RHIC

Author: STAR Collaboration, Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderóndela Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We report on the measurements of directed flow $v_1$ and elliptic flow $v_2$ for hadrons ($\pi^{\pm}$, $K^{\pm}$, $K_{S}^0$, $p$, $\phi$, $\Lambda$ and $\Xi^{-}$) from Au+Au collisions at $\sqrt{s_{NN}}$ = 3\,GeV and $v_{2}$ for ($\pi^{\pm}$, $K^{\pm}$, $p$ and $\overline{p}$) at 27 and 54.4\,GeV with the STAR experiment. While at the two higher energy midcentral collisions the number-of-constituent-quark (NCQ) scaling holds, at 3\,GeV the $v_{2}$ at midrapidity is negative for all hadrons and the NCQ scaling is absent. In addition, the $v_1$ slopes at midrapidity for almost all observed hadrons are found to be positive, implying dominant repulsive baryonic interactions. The features of negative $v_2$ and positive $v_1$ slope at 3\,GeV can be reproduced with a baryonic mean-field in transport model calculations. These results imply that the medium in such collisions is likely characterized by baryonic interactions., Comment: 8 pages, 5 figures
Published: 2021
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28. Global $\Lambda$-hyperon polarization in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV

Author: Abdallah, M. S., Aboona, B. E., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Calderó, M., Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csaná, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dixit, P., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoł, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Ko, H. S., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X. F., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pan, J., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pinté, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Sö, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Global hyperon polarization, $\overline{P}_\mathrm{H}$, in Au+Au collisions over a large range of collision energy, $\sqrt{s_\mathrm{NN}}$, was recently measured and successfully reproduced by hydrodynamic and transport models with intense fluid vorticity of the quark-gluon plasma. While na\"{i}ve extrapolation of data trends suggests a large $\overline{P}_\mathrm{H}$ as the collision energy is reduced, the behavior of $\overline{P}_\mathrm{H}$ at small $\sqrt{s_\mathrm{NN}}<7.7$ GeV is unknown. Operating the STAR experiment in fixed-target mode, we measured the polarization of $\Lambda$ hyperons along the direction of global angular momentum in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV. The observation of substantial polarization of $4.91\pm0.81(\rm stat.)\pm0.15(\rm syst.)$% in these collisions may require a reexamination of the viscosity of any fluid created in the collision, of the thermalization timescale of rotational modes, and of hadronic mechanisms to produce global polarization., Comment: 9 pages, 6 figures
Published: 2021
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29. Search for the chiral magnetic effect via charge-dependent azimuthal correlations relative to spectator and participant planes in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: The chiral magnetic effect (CME) refers to charge separation along a strong magnetic field due to imbalanced chirality of quarks in local parity and charge-parity violating domains in quantum chromodynamics. The experimental measurement of the charge separation is made difficult by the presence of a major background from elliptic azimuthal anisotropy. This background and the CME signal have different sensitivities to the spectator and participant planes, and could thus be determined by measurements with respect to these planes. We report such measurements in Au+Au collisions at a nucleon-nucleon center-of-mass energy of 200 GeV at the Relativistic Heavy-Ion Collider. It is found that the charge separation, with the flow background removed, is consistent with zero in peripheral (large impact parameter) collisions. Some indication of finite CME signals is seen in mid-central (intermediate impact parameter) collisions. Significant residual background effects may, however, still be present., Comment: PRL published version
Published: 2021
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30. Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at $\sqrt{s_{\rm NN}}=$ 27, 54.4, and 200 GeV at RHIC

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: According to first principle Lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region $\mu_{\rm B}\leq T_{c}$. In this range the ratio, $C_{6}/C_{2}$, of net-baryon distributions are predicted to be negative. In this paper, we report the first measurement of the midrapidity net-proton $C_{6}/C_{2}$ from 27, 54.4 and 200 GeV Au+Au collisions at RHIC. The dependence on collision centrality and kinematic acceptance in ($p_{T}$, $y$) are analyzed. While for 27 and 54.4 GeV collisions the $C_{6}/C_{2}$ values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the $C_{6}/C_{2}$ ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high energy nuclear collisions at top RHIC energy., Comment: 10 pages, 7 figures, 2 tables (published version)
Published: 2021

31. Invariant Jet Mass Measurements in $pp$ Collisions at $\sqrt{s} = 200$ GeV at RHIC

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We present the first inclusive measurements of the invariant and SoftDrop jet mass in proton-proton collisions at $\sqrt{s}=200$ GeV at STAR. The measurements are fully corrected for detector effects, and reported differentially in both the jet transverse momentum and jet radius parameter. We compare the measurements to established leading-order Monte Carlo event generators and find that STAR-tuned PYTHIA-6 reproduces the data, while LHC tunes of PYTHIA-8 and HERWIG-7 do not agree with the data, providing further constraints on parameter tuning. Finally, we observe that SoftDrop grooming, for which the contribution of wide-angle non-perturbative radiation is suppressed, shifts the jet mass distributions into closer agreement with the partonic jet mass as determined by both PYTHIA-8 and a next-to-leading-logarithmic accuracy perturbative QCD calculation. These measurements complement recent LHC measurements in a different kinematic region, as well as establish a baseline for future jet mass measurements in heavy-ion collisions at RHIC., Comment: 13 pages, 7 figures
Published: 2021
Full Text: View/download PDF

32. Azimuthal anisotropy measurements of strange and multistrange hadrons in U+U collisions at $\sqrt{s_{NN}} = 193$ GeV at the BNL Relativistic Heavy Ion Collider

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dong, X., Drachenberg, J. L., Duckworth, E., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Roy, D., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We present systematic measurements of azimuthal anisotropy for strange and multistrange hadrons ($K^{0}_{s}$, $\Lambda$, $\Xi$, and $\Omega$) and $\phi$ mesons at midrapidity ($|y| <$ 1.0) in collisions of U + U nuclei at $\sqrt{s_{NN}} = 193$ GeV, recorded by the STAR detector at the Relativistic Heavy Ion Collider. Transverse momentum ($p_{\text{T}}$) dependence of flow coefficients ($v_{2}$, $v_{3}$, and $v_{4}$) is presented for minimum bias collisions and three different centrality intervals. Number of constituent quark scaling of the measured flow coefficients in U + U collisions is discussed. We also present the ratio of $v_{n}$ scaled by the participant eccentricity ($\varepsilon_{n}\left\lbrace 2 \right\rbrace$) to explore system size dependence and collectivity in U + U collisions. The magnitude of $v_{2}/\varepsilon_{2}$ is found to be smaller in U + U collisions than that in central Au + Au collisions contradicting naive eccentricity scaling. Furthermore, the ratios between various flow harmonics ($v_{3}/v_{2}^{3/2}$, $v_{4}/v_{2}^{4/2}$) are studied and compared with hydrodynamic and transport model calculations., Comment: 22 pages, 16 figures
Published: 2021
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33. Cumulants and Correlation Functions of Net-proton, Proton and Antiproton Multiplicity Distributions in Au+Au Collisions at energies available at the BNL Relativistic Heavy Ion Collider

Author: STAR Collaboration, Abdallah, M. S., Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, I., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Baker, W., Cap, J. G. Ball, Barish, K., Behera, A., Bellwied, R., Bhagat, P., Bhasin, A., Bielcik, J., Bielcikova, J., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Cai, X. Z., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F. -H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Dhamija, A., Di Carlo, L., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fawzi, F. M., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Han, Y., Harabasz, S., Harasty, M. D., Harris, J. W., Harrison, H., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hu, Y., Huang, H., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Huang, Y., Humanic, T. J., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kisel, I., Kiselev, A., Knospe, A. G., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, X., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Loyd, E., Lukow, N. S., Luo, X., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Morozov, D. A., Mukherjee, A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nishitani, R., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Pandey, A. K., Panebratsev, Y., Parfenov, P., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Ponimatkin, G., Porter, J., Posik, M., Prozorova, V., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Racz, C., Radhakrishnan, S. K., Raha, N., Ray, R. L., Reed, R., Ritter, H. G., Robotkova, M., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shao, T., Sheikh, A. I., Shen, D., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Skoby, M. J., Smirnov, N., Söhngen, Y., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Sweger, Z. W., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Truhlar, T., Trzeciak, B. A., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Verkest, V., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, J., Wu, Y., Xi, B., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: We report a systematic measurement of cumulants, $C_{n}$, for net-proton, proton and antiproton multiplicity distributions, and correlation functions, $\kappa_n$, for proton and antiproton multiplicity distributions up to the fourth order in Au+Au collisions at $\sqrt{s_{\mathrm {NN}}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, 54.4, 62.4 and 200 GeV. The $C_{n}$ and $\kappa_n$ are presented as a function of collision energy, centrality and kinematic acceptance in rapidity, $y$, and transverse momentum, $p_{T}$. The data were taken during the first phase of the Beam Energy Scan (BES) program (2010 -- 2017) at the BNL Relativistic Heavy Ion Collider (RHIC) facility. The measurements are carried out at midrapidity ($|y| <$ 0.5) and transverse momentum 0.4 $<$ $p_{\rm T}$ $<$ 2.0 GeV/$c$, using the STAR detector at RHIC. We observe a non-monotonic energy dependence ($\sqrt{s_{\mathrm {NN}}}$ = 7.7 -- 62.4 GeV) of the net-proton $C_{4}$/$C_{2}$ with the significance of 3.1$\sigma$ for the 0-5\% central Au+Au collisions. This is consistent with the expectations of critical fluctuations in a QCD-inspired model. Thermal and transport model calculations show a monotonic variation with $\sqrt{s_{\mathrm {NN}}}$. For the multiparticle correlation functions, we observe significant negative values for a two-particle correlation function, $\kappa_2$, of protons and antiprotons, which are mainly due to the effects of baryon number conservation. Furthermore, it is found that the four-particle correlation function, $\kappa_4$, of protons plays a role in determining the energy dependence of proton $C_4/C_1$ below 19.6 GeV, which cannot be understood by the effect of baryon number conservation., Comment: 34 pages, 25 figures, 8 tables
Published: 2021
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34. Observation of $D_{s}^{\pm}/D^0$ enhancement in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$ = 200 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fu, C., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, W. Q., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment
Abstract: We report on the first measurement of charm-strange meson $D_s^{\pm}$ production at midrapidity in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$ = 200 GeV from the STAR experiment. The yield ratio between strange ($D_{s}^{\pm}$) and non-strange ($D^{0}$) open-charm mesons is presented and compared to model calculations. A significant enhancement, relative to a PYTHIA simulation of $p$+$p$ collisions, is observed in the $D_{s}^{\pm}/D^0$ yield ratio in Au+Au collisions over a large range of collision centralities. Model calculations incorporating abundant strange-quark production in the quark-gluon plasma (QGP) and coalescence hadronization qualitatively reproduce the data. The transverse-momentum integrated yield ratio of $D_{s}^{\pm}/D^0$ at midrapidity is consistent with a prediction from a statistical hadronization model with the parameters constrained by the yields of light and strange hadrons measured at the same collision energy. These results suggest that the coalescence of charm quarks with strange quarks in the QGP plays an important role in $D_{s}^{\pm}$ meson production in heavy-ion collisions.
Published: 2021
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35. Global polarization of $\Xi$ and $\Omega$ hyperons in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, W. Q., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Global polarization of $\Xi$ and $\Omega$ hyperons has been measured for the first time in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV. The measurements of the $\Xi^-$ and $\bar{\Xi}^+$ hyperon polarization have been performed by two independent methods, via analysis of the angular distribution of the daughter particles in the parity violating weak decay $\Xi\rightarrow\Lambda+\pi$, as well as by measuring the polarization of the daughter $\Lambda$-hyperon, polarized via polarization transfer from its parent. The polarization, obtained by combining the results from the two methods and averaged over $\Xi^-$ and $\bar{\Xi}^+$, is measured to be $\langle P_\Xi \rangle = 0.47\pm0.10~({\rm stat.})\pm0.23~({\rm syst.})\,\%$ for the collision centrality 20\%-80\%. The $\langle P_\Xi \rangle$ is found to be slightly larger than the inclusive $\Lambda$ polarization and in reasonable agreement with a multi-phase transport model (AMPT). The $\langle P_\Xi \rangle$ is found to follow the centrality dependence of the vorticity predicted in the model, increasing toward more peripheral collisions. The global polarization of $\Omega$, $\langle P_\Omega \rangle = 1.11\pm0.87~({\rm stat.})\pm1.97~({\rm syst.})\,\%$ was obtained by measuring the polarization of daughter $\Lambda$ in the decay $\Omega \rightarrow \Lambda + K$, assuming the polarization transfer factor $C_{\Omega\Lambda}=1$., Comment: 7 pages, 3 figures, Accepted for publication in Physical Review Letters
Published: 2020
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36. Measurement of transverse single-spin asymmetries of $\pi^0$ and electromagnetic jets at forward rapidity in 200 and 500 GeV transversely polarized proton-proton collisions

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Ghimire, N., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Pokhrel, B. R., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, W. Q., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment
Abstract: The STAR Collaboration reports measurements of the transverse single-spin asymmetry (TSSA) of inclusive $\pi^0$ at center-of-mass energies ($\sqrt s$) of 200 GeV and 500 GeV in transversely polarized proton-proton collisions in the pseudo-rapidity region 2.7 to 4.0. The results at the two different energies show a continuous increase of the TSSA with Feynman-$x$, and, when compared to previous measurements, no dependence on $\sqrt s$ from 19.4 GeV to 500 GeV is found. To investigate the underlying physics leading to this large TSSA, different topologies have been studied. $\pi^0$ with no nearby particles tend to have a higher TSSA than inclusive $\pi^0$. The TSSA for inclusive electromagnetic jets, sensitive to the Sivers effect in the initial state, is substantially smaller, but shows the same behavior as the inclusive $\pi^0$ asymmetry as a function of Feynman-$x$. To investigate final-state effects, the Collins asymmetry of $\pi^0$ inside electromagnetic jets has been measured. The Collins asymmetry is analyzed for its dependence on the $\pi^0$ momentum transverse to the jet thrust axis and its dependence on the fraction of jet energy carried by the $\pi^0$. The asymmetry was found to be small in each case for both center-of-mass energies. All the measurements are compared to QCD-based theoretical calculations for transverse-momentum-dependent parton distribution functions and fragmentation functions. Some discrepancies are found, which indicates new mechanisms might be involved., Comment: after replying to referee's comments. minor changes
Published: 2020
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37. Comparison of transverse single-spin asymmetries for forward $\pi^{0}$ production in polarized $pp$, $p\rm{Al}$ and $p\rm{Au}$ collisions at nucleon pair c.m. energy $\sqrt{s_{\mathrm{NN}}}= 200$ GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, W. Q., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The STAR Collaboration reports a measurement of the transverse single-spin asymmetries, $A_{N}$, for neutral pions produced in polarized proton collisions with protons ($pp$), with aluminum nuclei ($p\rm{Al}$) and with gold nuclei ($p\rm{Au}$) at a nucleon-nucleon center-of-mass energy of 200 GeV. Neutral pions are observed in the forward direction relative to the transversely polarized proton beam, in the pseudo-rapidity region $2.7<\eta<3.8$. Results are presented for $\pi^0$s observed in the STAR FMS electromagnetic calorimeter in narrow Feynman x ($x_F$) and transverse momentum ($p_T$) bins, spanning the range $0.172.5$ GeV/$c$. It is further observed that the value of $A_N$ is significantly larger for events with a large-$p_T$ isolated $\pi^0$ than for events with a non-isolated $\pi^0$ accompanied by additional jet-like fragments. The nuclear dependence $r(A)$ is similar for isolated and non-isolated $\pi^0$ events.
Published: 2020
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38. Measurements of $W$ and $Z/\gamma^*$ cross sections and their ratios in $p+p$ collisions at RHIC

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Gou, X., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., He, Y., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., Ji, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, W. Q., Shi, S. S., Shi, Y., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Yu, Y., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We report on the $W$ and $Z/\gamma^*$ differential and total cross sections as well as the $W^+$/$W^-$ and $(W^+ + W^-)$/$(Z/\gamma^*)$ cross-section ratios measured by the STAR experiment at RHIC in $p+p$ collisions at $\sqrt{s} = 500$ GeV and $510$ GeV. The cross sections and their ratios are sensitive to quark and antiquark parton distribution functions. In particular, at leading order, the $W$ cross-section ratio is sensitive to the $\bar{d}/\bar{u}$ ratio. These measurements were taken at high $Q^2 \sim M_W^2,M_Z^2$ and can serve as input into global analyses to provide constraints on the sea quark distributions. The results presented here combine three STAR data sets from 2011, 2012, and 2013, accumulating an integrated luminosity of 350 pb$^{-1}$. We also assess the expected impact that our $W^+/W^-$ cross-section ratios will have on various quark distributions, and find sensitivity to the $\bar{u}-\bar{d}$ and $\bar{d}/\bar{u}$ distributions., Comment: Accepted to PRD 39 pages, 15 Figs., and 9 tables
Published: 2020
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39. Flow and interferometry results from Au+Au collisions at $\sqrt{\textit{s}_{NN}}$ = 4.5 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kozyra, L., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: The Beam Energy Scan (BES) program at the Relativistic Heavy Ion Collider (RHIC) was extended to energies below $\sqrt{\textit{s}_{NN}}$ = 7.7 GeV in 2015 by successful implementation of the fixed-target mode of operation in the STAR (Solenoidal Track At RHIC) experiment. In the fixed-target mode, ions circulate in one ring of the collider and interact with a stationary target at the entrance of the STAR Time Projection Chamber. The first results for Au+Au collisions at $\sqrt{\textit{s}_{NN}}$ = 4.5 GeV are presented, including directed and elliptic flow of identified hadrons, and radii from pion femtoscopy. The proton flow and pion femtoscopy results agree quantitatively with earlier measurements by Alternating Gradient Synchrotron experiments at similar energies. This validates running the STAR experiment in the fixed-target configuration. Pion directed and elliptic flow are presented for the first time at this beam energy. Pion and proton elliptic flow show behavior which hints at constituent quark scaling, but large error bars preclude reliable conclusions. The ongoing second phase of BES (BES-II) will provide fixed-target data sets with 100 times more events at each of several energies down to $\sqrt{\textit{s}_{NN}}$ = 3.0 GeV., Comment: 18 pages, 20 figures; Contexts and figure caption was modified, one reference was added to address the referee's comments
Published: 2020
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40. Beam-Energy Dependence of the Directed Flow of Deuterons in Au+Au Collisions

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: We present a measurement of the first-order azimuthal anisotropy, $v_1(y)$, of deuterons from Au+Au collisions at $\sqrt{s_{NN}}$ = 7.7, 11.5, 14.5, 19.6, 27, and 39 GeV recorded with the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The energy dependence of the $v_1(y)$ slope, $dv_{1}/dy|_{y=0}$, for deuterons, where $y$ is the rapidity, is extracted for semi-central collisions (10-40\% centrality) and compared to that of protons. While the $v_1(y)$ slopes of protons are generally negative for $\sqrt{s_{NN}} >$ 10 GeV, those for deuterons are consistent with zero, a strong enhancement of the $v_1(y)$ slope of deuterons is seen at the lowest collision energy (the largest baryon density) at $\sqrt{s_{NN}} =$ 7.7 GeV. In addition, we report the transverse momentum dependence of $v_1$ for protons and deuterons. The experimental results are compared with transport and coalescence models.
Published: 2020
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41. Measurement of inclusive J/$\psi$ polarization in p+p collisions at $\sqrt{s}$ = 200 GeV by the STAR experiment

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report on new measurements of inclusive J/$\psi$ polarization at mid-rapidity in p+p collisions at $\sqrt{s}$ = 200 GeV by the STAR experiment at RHIC. The polarization parameters, $\lambda_\theta$, $\lambda_\phi$, and $\lambda_{\theta\phi}$, are measured as a function of transverse momentum ($p_T$) in both the Helicity and Collins-Soper (CS) reference frames within $p_T< 10$ GeV/$C$. Except for $\lambda_\theta$ in the CS frame at the highest measured $p_T$, all three polarization parameters are consistent with 0 in both reference frames without any strong $p_T$ dependence. Several model calculations are compared with data, and the one using the Color Glass Condensate effective field theory coupled with non-relativistic QCD gives the best overall description of the experimental results, even though other models cannot be ruled out due to experimental uncertainties., Comment: 14 pages, 11 figures
Published: 2020
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42. Investigation of the linear and mode-coupled flow harmonics in Au+Au collisions at $\sqrt{\textit{s}_{NN}}$ = 200 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment
Abstract: Flow harmonics ($\textit{v}_{n}$) of the Fourier expansion for the azimuthal distributions of hadrons are commonly employed to quantify the azimuthal anisotropy of particle production relative to the collision symmetry planes. While lower order Fourier coefficients ($\textit{v}_{2}$ and $\textit{v}_{3}$) are more directly related to the corresponding eccentricities of the initial state, the higher-order flow harmonics ($\textit{v}_{n>3}$) can be induced by a mode-coupled response to the lower-order anisotropies, in addition to a linear response to the same-order anisotropies. These higher-order flow harmonics and their linear and mode-coupled contributions can be used to more precisely constrain the initial conditions and the transport properties of the medium in theoretical models. The multiparticle azimuthal cumulant method is used to measure the linear and mode-coupled contributions in the higher-order anisotropic flow, the mode-coupled response coefficients, and the correlations of the event plane angles for charged particles as functions of centrality and transverse momentum in Au+Au collisions at nucleon-nucleon center-of-mass energy $\sqrt{\textit{s}_{NN}}$ = 200 GeV. The results are compared to similar LHC measurements as well as to several viscous hydrodynamic calculations with varying initial conditions., Comment: 15 pages, 4 figures, submitted for publication
Published: 2020
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43. Pair invariant mass to isolate background in the search for the chiral magnetic effect in Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$= 200 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: Quark interactions with topological gluon configurations can induce local chirality imbalance and parity violation in quantum chromodynamics, which can lead to the chiral magnetic effect (CME) -- an electric charge separation along the strong magnetic field in relativistic heavy-ion collisions. The CME-sensitive azimuthal correlator observable ($\Delta\gamma$) is contaminated by background arising, in part, from resonance decays coupled with elliptic anisotropy ($v_{2}$). We report here differential measurements of the correlator as a function of the pair invariant mass ($m_{\rm inv}$) in 20-50\% centrality Au+Au collisions at $\sqrt{s_{_{\rm NN}}}$= 200 GeV by the STAR experiment at RHIC. Strong resonance background contributions to $\Delta\gamma$ are observed. At large $m_{\rm inv}$ where this background is significantly reduced, the $\Delta\gamma$ value is found to be significantly smaller. An event-shape-engineering technique is deployed to determine the $v_{2}$ background shape as a function of $m_{\rm inv}$. We extract a $v_2$-independent and $m_{\rm inv}$-averaged signal $\Delta\gamma_{\rm sig}$ = (0.03 $\pm$ 0.06 $\pm$ 0.08) $\times10^{-4}$, or $(2\pm4\pm5)\%$ of the inclusive $\Delta\gamma(m_{\rm inv}>0.4$ GeV/$c^2$)$ =(1.58 \pm 0.02 \pm 0.02) \times10^{-4}$, within pion $p_{T}$ = 0.2 - 0.8~\gevc and averaged over pseudorapidity ranges of $-1 < \eta < -0.05$ and $0.05 < \eta < 1$. This represents an upper limit of $0.23\times10^{-4}$, or $15\%$ of the inclusive result, at $95\%$ confidence level for the $m_{\rm inv}$-integrated CME contribution., Comment: PRC published version
Published: 2020
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44. Measurement of inclusive charged-particle jet production in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, P. M., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The STAR Collaboration at the Relativistic Heavy Ion Collider reports the first measurement of inclusive jet production in peripheral and central Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV. Jets are reconstructed with the anti-k$_{T}$ algorithm using charged tracks with pseudorapidity $|\eta|<1.0$ and transverse momentum $0.2
Published: 2020
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45. Measurement of the central exclusive production of charged particle pairs in proton-proton collisions at $\sqrt{s} = 200$ GeV with the STAR detector at RHIC

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report on the measurement of the Central Exclusive Production of charged particle pairs $h^{+}h^{-}$ ($h = \pi, K, p$) with the STAR detector at RHIC in proton-proton collisions at $\sqrt{s} = 200$ GeV. The charged particle pairs produced in the reaction $pp\to p^\prime+h^{+}h^{-}+p^\prime$ are reconstructed from the tracks in the central detector, while the forward-scattered protons are measured in the Roman Pot system. Differential cross sections are measured in the fiducial region, which roughly corresponds to the square of the four-momentum transfers at the proton vertices in the range $0.04~\mbox{GeV}^2 < -t_1 , -t_2 < 0.2~\mbox{GeV}^2$, invariant masses of the charged particle pairs up to a few GeV and pseudorapidities of the centrally-produced hadrons in the range $|\eta|<0.7$. The measured cross sections are compared to phenomenological predictions based on the Double Pomeron Exchange (DPE) model. Structures observed in the mass spectra of $\pi^{+}\pi^{-}$ and $K^{+}K^{-}$ pairs are consistent with the DPE model, while angular distributions of pions suggest a dominant spin-0 contribution to $\pi^{+}\pi^{-}$ production. The fiducial $\pi^+\pi^-$ cross section is extrapolated to the Lorentz-invariant region, which allows decomposition of the invariant mass spectrum into continuum and resonant contributions. The extrapolated cross section is well described by the continuum production and at least three resonances, the $f_0(980)$, $f_2(1270)$ and $f_0(1500)$, with a possible small contribution from the $f_0(1370)$. Fits to the extrapolated differential cross section as a function of $t_1$ and $t_2$ enable extraction of the exponential slope parameters in several bins of the invariant mass of $\pi^+\pi^-$ pairs. These parameters are sensitive to the size of the interaction region., Comment: Published in Journal of High Energy Physics
Published: 2020
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46. Results on Total and Elastic Cross Sections in Proton-Proton Collisions at $\sqrt{s} = 200$ GeV

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Bueltmann, S., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Chu, X., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harabasz, S., Harris, J. W., He, S., He, W., He, X. H., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Kumar, S., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nunes, A. S., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sheikh, A. I., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, X., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, C., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report results on the total and elastic cross sections in proton-proton collisions at $\sqrt{s}=200$ GeV obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section was measured in the squared four-momentum transfer range $0.045 \leq -t \leq 0.135$ GeV$^2$. The value of the exponential slope parameter $B$ of the elastic differential cross section $d\sigma/dt \sim e^{-Bt}$ in the measured $-t$ range was found to be $B = 14.32 \pm 0.09 (stat.)^{\scriptstyle +0.13}_{\scriptstyle -0.28} (syst.)$ GeV$^{-2}$. The total cross section $\sigma_{tot}$, obtained from extrapolation of the $d\sigma/dt$ to the optical point at $-t = 0$, is $\sigma_{tot} = 54.67 \pm 0.21 (stat.) ^{\scriptstyle +1.28}_{\scriptstyle -1.38} (syst.)$ mb. We also present the values of the elastic cross section $\sigma_{el} = 10.85 \pm 0.03 (stat.) ^{\scriptstyle +0.49}_{\scriptstyle -0.41}(syst.)$ mb, the elastic cross section integrated within the STAR $t$-range $\sigma^{det}_{el} = 4.05 \pm 0.01 (stat.) ^{\scriptstyle+0.18}_{\scriptstyle -0.17}(syst.)$ mb, and the inelastic cross section $\sigma_{inel} = 43.82 \pm 0.21 (stat.) ^{\scriptstyle +1.37}_{\scriptstyle -1.44} (syst.)$ mb. The results are compared with the world data., Comment: Updated version. New figure 4 and updated text. Accepted for publication in Phys. Lett. B
Published: 2020
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47. Measurement of Groomed Jet Substructure Observables in \pp Collisions at $\sqrt{s} = 200$ GeV with STAR

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harris, J. W., He, S., He, W., He, X., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: High Energy Physics - Experiment
Abstract: In this letter, measurements of the shared momentum fraction ($z_{\rm{g}}$) and the groomed jet radius ($R_{\rm{g}}$), as defined in the SoftDrop algorihm, are reported in \pp collisions at $\sqrt{s} = 200$ GeV collected by the STAR experiment. These substructure observables are differentially measured for jets of varying resolution parameters from $R = 0.2 - 0.6$ in the transverse momentum range $15 < p_{\rm{T, jet}} < 60$ GeV$/c$. These studies show that, in the $p_{\rm{T, jet}}$ range accessible at $\sqrt{s} = 200$ GeV and with increasing jet resolution parameter and jet transverse momentum, the $z_{\rm{g}}$ distribution asymptotically converges to the DGLAP splitting kernel for a quark radiating a gluon. The groomed jet radius measurements reflect a momentum-dependent narrowing of the jet structure for jets of a given resolution parameter, i.e., the larger the $p_{\rm{T, jet}}$, the narrower the first splitting. For the first time, these fully corrected measurements are compared to Monte Carlo generators with leading order QCD matrix elements and leading log in the parton shower, and to state-of-the-art theoretical calculations at next-to-leading-log accuracy. We observe that PYTHIA 6 with parameters tuned to reproduce RHIC measurements is able to quantitatively describe data, whereas PYTHIA 8 and HERWIG 7, tuned to reproduce LHC data, are unable to provide a simultaneous description of both $z_{\rm{g}}$ and $R_{\rm{g}}$, resulting in opportunities for fine parameter tuning of these models for \pp collisions at RHIC energies. We also find that the theoretical calculations without non-perturbative corrections are able to qualitatively describe the trend in data for jets of large resolution parameters at high $p_{\rm{T, jet}}$, but fail at small jet resolution parameters and low jet transverse momenta., Comment: published version. see journal website for supplemental material
Published: 2020
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48. Beam energy dependence of net-$\Lambda$ fluctuations measured by the STAR experiment at RHIC

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harris, J. W., He, S., He, W., He, X., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: The measurements of particle multiplicity distributions have generated considerable interest in understanding the fluctuations of conserved quantum numbers in the Quantum Chromodynamics (QCD) hadronization regime, in particular near a possible critical point and near the chemical freeze-out. We report the measurement of efficiency and centrality bin width corrected cumulant ratios ($C_{2}/C_{1}$, $C_{3}/C_{2}$) of net-$\Lambda$ distributions, in the context of both strangeness and baryon number conservation, as a function of collision energy, centrality and rapidity. The results are for Au + Au collisions at five beam energies ($\sqrt{s_{NN}}$ = 19.6, 27, 39, 62.4 and 200 GeV) recorded with the Solenoidal Tracker at RHIC (STAR). We compare our results to the Poisson and negative binomial (NBD) expectations, as well as to Ultra-relativistic Quantum Molecular Dynamics (UrQMD) and Hadron Resonance Gas (HRG) model predictions. Both NBD and Poisson baselines agree with data within the statistical and systematic uncertainties. The ratios of the measured cumulants show no features of critical fluctuations. The chemical freeze-out temperatures extracted from a recent HRG calculation, which was successfully used to describe the net-proton, net-kaon and net-charge data, indicate $\Lambda$ freeze-out conditions similar to those of kaons. However, large deviations are found when comparing to temperatures obtained from net-proton fluctuations. The net-$\Lambda$ cumulants show a weak, but finite, dependence on the rapidity coverage in the acceptance of the detector, which can be attributed to quantum number conservation., Comment: 12 pages, 9 figures, 3 tables, submitted to Phys.Rev.C
Published: 2020
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49. Non-monotonic energy dependence of net-proton number fluctuations

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harris, J. W., He, S., He, W., He, X., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: Non-monotonic variation with collision energy ($\sqrt{s_{\rm NN}}$) of the moments of the net-baryon number distribution in heavy-ion collisions, related to the correlation length and the susceptibilities of the system, is suggested as a signature for the Quantum Chromodynamics (QCD) critical point. We report the first evidence of a non-monotonic variation in kurtosis times variance of the net-proton number (proxy for net-baryon number) distribution as a function of \rootsnn with 3.1$\sigma$ significance, for head-on (central) gold-on-gold (Au+Au) collisions measured using the STAR detector at RHIC. Data in non-central Au+Au collisions and models of heavy-ion collisions without a critical point show a monotonic variation as a function of $\sqrt{s_{\rm NN}}$., Comment: 12 Pages, 9 Figures and 5 Tables (published version)
Published: 2020
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50. Underlying event measurements in $p$+$p$ collisions at $\sqrt{s}= 200 $ GeV at RHIC

Author: STAR Collaboration, Adam, J., Adamczyk, L., Adams, J. R., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aparin, A., Aschenauer, E. C., Ashraf, M. U., Atetalla, F. G., Attri, A., Averichev, G. S., Bairathi, V., Barish, K., Behera, A., Bellwied, R., Bhasin, A., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Brandenburg, J. D., Brandin, A. V., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Chakaberia, I., Chaloupka, P., Chan, B. K., Chang, F-H., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chen, D., Chen, J. H., Chen, X., Chen, Z., Cheng, J., Cherney, M., Chevalier, M., Choudhury, S., Christie, W., Crawford, H. J., Csanád, M., Daugherity, M., Dedovich, T. G., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dong, X., Drachenberg, J. L., Dunlop, J. C., Edmonds, T., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, A., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, C. J., Feng, Y., Filip, P., Finch, E., Fisyak, Y., Francisco, A., Fulek, L., Gagliardi, C. A., Galatyuk, T., Geurts, F., Gibson, A., Gopal, K., Grosnick, D., Guryn, W., Hamad, A. I., Hamed, A., Harris, J. W., He, S., He, W., He, X., Heppelmann, S., Herrmann, N., Hoffman, E., Holub, L., Hong, Y., Horvat, S., Hu, Y., Huang, H. Z., Huang, S. L., Huang, T., Huang, X., Humanic, T. J., Huo, P., Igo, G., Isenhower, D., Jacobs, W. W., Jena, C., Jentsch, A., JI, Y., Jia, J., Jiang, K., Jowzaee, S., Ju, X., Judd, E. G., Kabana, S., Kabir, M. L., Kagamaster, S., Kalinkin, D., Kang, K., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kelsey, M., Khyzhniak, Y. V., Kikoła, D. P., Kim, C., Kimelman, B., Kincses, D., Kinghorn, T. A., Kisel, I., Kiselev, A., Kisiel, A., Kocan, M., Kochenda, L., Kosarzewski, L. K., Kramarik, L., Kravtsov, P., Krueger, K., Mudiyanselage, N. Kulathunga, Kumar, L., Elayavalli, R. Kunnawalkam, Kwasizur, J. H., Lacey, R., Lan, S., Landgraf, J. M., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Leung, Y. H., Li, C., Li, W., Li, X., Li, Y., Liang, Y., Licenik, R., Lin, T., Lin, Y., Lisa, M. A., Liu, F., Liu, H., Liu, P., Liu, T., Liu, X., Liu, Y., Liu, Z., Ljubicic, T., Llope, W. J., Longacre, R. S., Lukow, N. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mazer, J. A., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mooney, I., Moravcova, Z., Morozov, D. A., Nagy, M., Nam, J. D., Nasim, Md., Nayak, K., Neff, D., Nelson, J. M., Nemes, D. B., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Odyniec, G., Ogawa, A., Oh, S., Okorokov, V. A., Page, B. S., Pak, R., Pandav, A., Panebratsev, Y., Pawlik, B., Pawlowska, D., Pei, H., Perkins, C., Pinsky, L., Pintér, R. L., Pluta, J., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Radhakrishnan, S. K., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Sahoo, N. R., Sako, H., Salur, S., Sandweiss, J., Sato, S., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seck, F., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, F., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singh, J., Singha, S., Smirnov, N., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stefaniak, M., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sumbera, M., Summa, B., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Szymanski, P., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Tomkiel, C. A., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Tu, Z., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., Vanek, J., Vasiliev, A. N., Vassiliev, I., Videbæk, F., Vokal, S., Voloshin, S. A., Wang, F., Wang, G., Wang, J. S., Wang, P., Wang, Y., Wang, Z., Webb, J. C., Weidenkaff, P. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xu, H., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Y., Xu, Z., Yang, C., Yang, Q., Yang, S., Yang, Y., Yang, Z., Ye, Z., Yi, L., Yip, K., Zbroszczyk, H., Zha, W., Zhang, D., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. J., Zhang, Z., Zhao, J., Zhong, C., Zhou, C., Zhu, X., Zhu, Z., Zurek, M., and Zyzak, M.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: Particle production sensitive to non-factorizable and non-perturbative processes that contribute to the underlying event associated with a high transverse momentum ($p_{T}$) jet in proton+proton collisions at $\sqrt{s}$=200 GeV is studied with the STAR detector. Each event is divided into three regions based on the azimuthal angle with respect to the highest-$p_{T}$ jet direction: in the leading jet direction ("Toward"), opposite to the leading jet ("Away"), and perpendicular to the leading jet ("Transverse"). In the Transverse region, the average charged particle density is found to be between 0.4 and 0.6 and the mean transverse momentum, $\langle p_{T}\rangle$, between 0.5-0.7 GeV/$c$ for particles with $p_{T}$$>$0.2 GeV/$c$ at mid-pseudorapidity ($|\eta|$$<$1) and jet $p_{T}$$>$15 GeV/$c$. Both average particle density and $\langle p_{T}\rangle$ depend weakly on the leading jet $p_{T}$. Closer inspection of the Transverse region hints that contributions to the underlying event from initial- and final-state radiation are significantly smaller in these collisions than at the higher energies, up to 13 TeV, recorded at the LHC. Underlying event measurements associated with a high-$p_{T}$ jet will contribute to our understanding of QCD processes at hard and soft scales at RHIC energies, as well as provide constraints to modeling of underlying event dynamics.
Published: 2019
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