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5. Towards controllable Si-doping in oxide molecular beam epitaxy using a solid SiO source: Application to $\beta$-Ga2O3

Author

Ardenghi, A., Bierwagen, O., Falkenstein, A., Hoffmann, G., Lähnemann, J., Martin, M., and Mazzolini, P.

Subjects
Condensed Matter - Materials Science, Physics - Applied Physics
Abstract

The oxidation-related issues in controlling Si doping from the Si source material in oxide molecular beam epitaxy (MBE) is addressed by using solid SiO as an alternative source material in a conventional effusion cell. Line-of-sight quadrupole mass spectrometry of the direct SiO-flux ($\Phi_{SiO}$) from the source at different temperatures ($T_{SiO}$) confirmed SiO molecules to sublime with an activation energy of 3.3eV. The $T_{SiO}$-dependent $\Phi_{SiO}$ was measured in vacuum before and after subjecting the source material to an O$_{2}$-background of $10^{-5}$ mbar (typical oxide MBE regime). The absence of a significant $\Phi_{SiO}$ difference indicates negligible source oxidation in molecular O$_{2}$. Mounted in an oxygen plasma-assisted MBE, Si-doped $\beta$-Ga2O3 layers were grown using this source. The $\Phi_{SiO}$ at the substrate was evaluated [from 2.9x10$^{9}$ cm$^{-2}$s$^{-1}$ ($T_{SiO}$=700{\deg}C) to 5.5x10$^{13}$ cm$^{-2}$s$^{-1}$ (T$_{SiO}$=1000{\deg}C)] and Si-concentration in the $\beta$-Ga2O3 layers measured by secondary ion mass spectrometry highlighting unprecedented control of continuous Si-doping for oxide MBE, i.e., $N_{Si}$ from 4x10$^{17}$ cm$^{-3}$ ($T_{SiO}$=700{\deg}C) up to 1.7x10$^{20}$ cm$^{-3}$ ($T_{SiO}$=900{\deg}C). For a homoepitaxial $\beta$-Ga2O3 layer an Hall charge carrier concentration of 3x10$^{19}$ cm$^{-3}$ in line with the provided $\Phi_{SiO}$ ($T_{SiO}$=800{\deg}C) is demonstrated. No SiO-incorporation difference was found between $\beta$-Ga2O3(010) layers homoepitaxially grown at 750{\deg}C and $\beta$-Ga2O3(-201) layers heteroepitaxially grown at 550{\deg}C. The presence of activated oxygen (plasma) resulted in partial source oxidation and related decrease of doping concentration (particularly at $T_{SiO}$<800{\deg}C) which has been tentatively explained with a simple model. Degassing the source at 1100{\deg}C reverted the oxidation.

Published
2022
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7. Coherent diffractive photoproduction of $\rho^{0}$ mesons on gold nuclei at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fujita, J., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, B., Huang, T., Huang, H. Z., Huang, X., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Klein, S. R., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, X., Li, C., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, Y., Liu, F., Liu, H., Liu, P., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, Y. G., Ma, L., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The STAR Collaboration reports on the photoproduction of $\pi^+\pi^-$ pairs in gold-gold collisions at a center-of-mass energy of 200 GeV/nucleon-pair. These pion pairs are produced when a nearly-real photon emitted by one ion scatters from the other ion. We fit the $\pi^+\pi^-$ invariant mass spectrum with a combination of $\rho$ and $\omega$ resonances and a direct $\pi^+\pi^-$ continuum. This is the first observation of the $\omega$ in ultra-peripheral collisions, and the first measurement of $\rho-\omega$ interference at energies where photoproduction is dominated by Pomeron exchange. The $\omega$ amplitude is consistent with the measured $\gamma p\rightarrow \omega p$ cross section, a classical Glauber calculation and the $\omega\rightarrow\pi^+\pi^-$ branching ratio. The $\omega$ phase angle is similar to that observed at much lower energies, showing that the $\rho-\omega$ phase difference does not depend significantly on photon energy. The $\rho^0$ differential cross section $d\sigma/dt$ exhibits a clear diffraction pattern, compatible with scattering from a gold nucleus, with 2 minima visible. The positions of the diffractive minima agree better with the predictions of a quantum Glauber calculation that does not include nuclear shadowing than with a calculation that does include shadowing., Comment: 24 pages with 9 figures

Published
2017
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8. Bulk Properties of the Medium Produced in Relativistic Heavy-Ion Collisions from the Beam Energy Scan Program

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, H., Liu, P., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We present measurements of bulk properties of the matter produced in Au+Au collisions at $\sqrt{s_{NN}}=$ 7.7, 11.5, 19.6, 27, and 39 GeV using identified hadrons ($\pi^\pm$, $K^\pm$, $p$ and $\bar{p}$) from the STAR experiment in the Beam Energy Scan (BES) Program at the Relativistic Heavy Ion Collider (RHIC). Midrapidity ($|y|<$0.1) results for multiplicity densities $dN/dy$, average transverse momenta $\langle p_T \rangle$ and particle ratios are presented. The chemical and kinetic freeze-out dynamics at these energies are discussed and presented as a function of collision centrality and energy. These results constitute the systematic measurements of bulk properties of matter formed in heavy-ion collisions over a broad range of energy (or baryon chemical potential) at RHIC., Comment: 35 pages, 38 figures

Published
2017
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9. Constraining the initial conditions and temperature dependent transport with three-particle correlations in Au+Au collisions

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, H., Liu, P., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

We present three-particle mixed-harmonic correlations $\la \cos (m\phi_a + n\phi_b - (m+n) \phi_c)\ra$ for harmonics $m,n=1-3$ for charged particles in $\sqrt{s_{NN}}=$200 GeV Au+Au collisions at RHIC. These measurements provide information on the three-dimensional structure of the initial collision zone and are important for constraining models of a subsequent low-viscosity quark-gluon plasma expansion phase. We investigate correlations between the first, second and third harmonics predicted as a consequence of fluctuations in the initial state. The dependence of the correlations on the pseudorapidity separation between particles show hints of a breaking of longitudinal invariance. We compare our results to a number of state-of-the art hydrodynamic calculations with different initial states and temperature dependent viscosities. These measurements provide important steps towards constraining the temperature dependent transport and the longitudinal structure of the initial state at RHIC., Comment: 8 pages, 4 figures, v2 : a new figure, texts & references added

Published
2017
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10. Harmonic decomposition of three-particle azimuthal correlations at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, H., Liu, P., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

We present measurements of three-particle correlations for various harmonics in Au+Au collisions at energies ranging from $\sqrt{s_{{\rm NN}}}=7.7$ to 200 GeV using the STAR detector. The quantity $\langle\cos(m\phi_1+n\phi_2-(m+n)\phi_3)\rangle$ is evaluated as a function of $\sqrt{s_{{\rm NN}}}$, collision centrality, transverse momentum, $p_T$, pseudo-rapidity difference, $\Delta\eta$, and harmonics ($m$ and $n$). These data provide detailed information on global event properties like the three-dimensional structure of the initial overlap region, the expansion dynamics of the matter produced in the collisions, and the transport properties of the medium. A strong dependence on $\Delta\eta$ is observed for most harmonic combinations consistent with breaking of longitudinal boost invariance. Data reveal changes with energy in the two-particle correlation functions relative to the second-harmonic event-plane and provide ways to constrain models of heavy-ion collisions over a wide range of collision energies., Comment: 19 pages, 15 figures, v2 : additional texts and references added

Published
2017
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11. Measurement of $D^0$ azimuthal anisotropy at mid-rapidity in Au+Au collisions at \sNN = 200\,GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, H., Liu, P., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We report the first measurement of the elliptic anisotropy ($v_2$) of the charm meson $D^0$ at mid-rapidity ($|y|$\,$<$\,1) in Au+Au collisions at \sNN = 200\,GeV. The measurement was conducted by the STAR experiment at RHIC utilizing a new high-resolution silicon tracker. The measured $D^0$ $v_2$ in 0--80\% centrality Au+Au collisions can be described by a viscous hydrodynamic calculation for transverse momentum ($p_{\rm T}$) less than 4\,GeV/$c$. The $D^0$ $v_2$ as a function of transverse kinetic energy ($m_{\rm T} - m_0$, where $m_{\rm T} = \sqrt{p_{\rm T}^2 + m_0^2}$) is consistent with that of light mesons in 10--40\% centrality Au+Au collisions. These results suggest that charm quarks have achieved local thermal equilibrium with the medium created in such collisions. Several theoretical models, with the temperature--dependent, dimensionless charm spatial diffusion coefficient ($2{\pi}TD_s$) in the range of $\sim$2--12, are able to simultaneously reproduce our $D^0$ $v_2$ result and our previously published results for the $D^0$ nuclear modification factor., Comment: 7 pages, 4 figures, submitted to PRL

Published
2017
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14. Measurement of the cross section and longitudinal double-spin asymmetry for di-jet production in polarized $pp$ collisions at $\sqrt{s}$ = 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fujita, J., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, B., Huang, T., Huang, H. Z., Huang, X., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, X., Li, C., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, Y., Liu, F., Liu, H., Liu, P., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, Y. G., Ma, L., Ma, R., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report the first measurement of the longitudinal double-spin asymmetry $A_{LL}$ for mid-rapidity di-jet production in polarized $pp$ collisions at a center-of-mass energy of $\sqrt{s} = 200$ GeV. The di-jet cross section was measured and is shown to be consistent with next-to-leading order (NLO) perturbative QCD predictions. $A_{LL}$ results are presented for two distinct topologies, defined by the jet pseudorapidities, and are compared to predictions from several recent NLO global analyses. The measured asymmetries, the first such correlation measurements, support those analyses that find positive gluon polarization at the level of roughly 0.2 over the region of Bjorken-$x > 0.05$., Comment: 8 pages, 4 figures, 1 table Contains changes requested by journal referees

Published
2016
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15. Di-Jet Imbalance Measurements at $\sqrt{s_{NN}} = 200$ GeV at STAR

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, X., Huang, B., Huang, H. Z., Huang, T., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, X., Li, Y., Li, C., Lin, T., Lisa, M. A., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Luo, S., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, A., Sharma, B., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, X. M., Sun, Z., Sun, Y., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, F., Wang, J. S., Wang, G., Wang, Y., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xin, K., Xu, Q. H., Xu, H., Xu, Y. F., Xu, Z., Xu, J., Xu, N., Yang, S., Yang, Q., Yang, Y., Yang, C., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, J., Zhang, Z., Zhang, S., Zhang, J. B., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We report the first di-jet transverse momentum asymmetry measurements from Au+Au and p+p collisions at RHIC. The two highest-energy back-to-back jets reconstructed from fragments with transverse momenta above 2 GeV/c display a significantly stronger momentum imbalance in heavy-ion collisions than in the p+p reference. When re-examined with correlated soft particles included, we observe that these di-jets then exhibit a unique new feature -- momentum balance is restored to that observed in p+p for a jet resolution parameter of R=0.4, while re-balancing is not attained with a smaller value of R=0.2., Comment: 7 pages, 3 figures. To be submitted to PRL

Published
2016
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16. Upsilon production in U+U collisions at 193 GeV with the STAR experiment

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, H. Z., Huang, B., Huang, T., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, Y., Li, C., Li, X., Li, W., Lin, T., Lisa, M. A., Liu, F., Liu, Y., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Luo, S., Ma, G. L., Ma, R., Ma, L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, A., Sharma, B., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, Z., Sun, X. M., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, J. S., Wang, F., Wang, Y., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xin, K., Xu, Z., Xu, H., Xu, N., Xu, J., Xu, Y. F., Xu, Q. H., Yang, Y., Yang, S., Yang, Q., Yang, C., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J., Zhang, Z., Zhang, S., Zhang, X. P., Zhang, J. B., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We present a measurement of the inclusive production of Upsilon mesons in U+U collisions at 193 GeV at mid-rapidity (|y| < 1). Previous studies in central Au+Au collisions at 200 GeV show a suppression of Upsilon(1S+2S+3S) production relative to expectations from the Upsilon yield in p+p collisions scaled by the number of binary nucleon-nucleon collisions (Ncoll), with an indication that the Upsilon(1S) state is also suppressed. The present measurement extends the number of participant nucleons in the collision (Npart) by 20% compared to Au+Au collisions, and allows us to study a system with higher energy density. We observe a suppression in both the Upsilon(1S+2S+3S) and Upsilon(1S) yields in central U+U data, which consolidates and extends the previously observed suppression trend in Au+Au collisions., Comment: 9 pages, 8 figures. Accepted in Phys.Rev.C

Published
2016
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17. Charge-dependent directed flow in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huang, T., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, Y., Li, C., Li, W., Li, X., Lin, T., Lisa, M. A., Liu, Y., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Luo, S., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Z., Sun, Y., Sun, X. M., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, F., Wang, J. S., Wang, Y., Wang, H., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, Q. H., Xu, Y. F., Xu, H., Xu, Z., Xu, N., Xu, J., Yang, C., Yang, Y., Yang, S., Yang, Q., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J., Zhang, X. P., Zhang, S., Zhang, Y., Zhang, J. B., Zhang, Z., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We present the first measurement of charge-dependent directed flow in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV. The results are presented as a function of the particle transverse momentum and pseudorapidity for different centralities. A finite difference between the directed flow of positive and negative charged particles is observed that qualitatively agrees with the expectations from the effects of the initial strong electric field between two colliding ions with different nuclear charges. The measured difference in directed flow is much smaller than that obtained from the parton-hadron-string-dynamics (PHSD) model, which suggests that most of the electric charges, i.e. quarks and antiquarks, have not yet been created during the lifetime of the strong electric field, which is of the order of, or less than, 1fm/$c$., Comment: 8 pages, 4 figures, Accepted for publication in Phys. Rev. Lett

Published
2016
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18. Energy dependence of $J/\psi$ production in Au+Au collisions at $\sqrt{s_{NN}} =$ 39, 62.4 and 200 GeV

Author

Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, Y., Li, C., Li, W., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Luo, S., Ma, G. L., Ma, L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Y., Sun, Z., Sun, X. M., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, H., Wang, F., Wang, Y., Wang, J. S., Wang, G., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, N., Xu, Q. H., Xu, Z., Xu, J., Xu, H., Xu, Y. F., Yang, S., Yang, Y., Yang, C., Yang, Q., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, J. B., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, J., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

The inclusive $J/\psi$ transverse momentum ($p_{T}$) spectra and nuclear modification factors are reported at midrapidity ($|y|<1.0$) in Au+Au collisions at $\sqrt{s_{NN}}=$ 39, 62.4 and 200 GeV taken by the STAR experiment. A suppression of $J/\psi$ production, with respect to {\color{black}the production in $p+p$ scaled by the number of binary nucleon-nucleon collisions}, is observed in central Au+Au collisions at these three energies. No significant energy dependence of nuclear modification factors is found within uncertainties. The measured nuclear modification factors can be described by model calculations that take into account both suppression of direct $J/\psi$ production due to the color screening effect and $J/\psi$ regeneration from recombination of uncorrelated charm-anticharm quark pairs.

Published
2016
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19. Near-side azimuthal and pseudorapidity correlations using neutral strange baryons and mesons in d+Au, Cu+Cu and Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Author

STAR Collaboration, Abelev, B., Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Barnby, L. S., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bombara, M., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Gaillard, L., Geurts, D. Garand F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, X., Huang, B., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Jones, P. G., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, Y., Li, W., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, R., Ma, G. L., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nattrass, C., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Z., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæ, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, F., Wang, G., Wang, J. S., Wang, H., Wang, Y., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, Y. F., Xu, Q. H., Xu, N., Xu, H., Xu, Z., Xu, J., Yang, S., Yang, Y., Yang, C., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, Y., Zhang, J., Zhang, S., Zhang, Z., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We present measurements of the near-side of triggered di-hadron correlations using neutral strange baryons ($\Lambda$, $\bar{\Lambda}$) and mesons ($K^0_S$) at intermediate transverse momentum (3 $<$ $p_T$ $<$ 6 GeV/$c$) to look for possible flavor and baryon/meson dependence. This study is performed in $d$+Au, Cu+Cu and Au+Au collisions at $\sqrt{s_{{NN}}}$ = 200 GeV measured by the STAR experiment at RHIC. The near-side di-hadron correlation contains two structures, a peak which is narrow in azimuth and pseudorapidity consistent with correlations due to jet fragmentation, and a correlation in azimuth which is broad in pseudorapidity. The particle composition of the jet-like correlation is determined using identified associated particles. The dependence of the conditional yield of the jet-like correlation on the trigger particle momentum, associated particle momentum, and centrality for correlations with unidentified trigger particles are presented. The neutral strange particle composition in jet-like correlations with unidentified charged particle triggers is not well described by PYTHIA. However, the yield of unidentified particles in jet-like correlations with neutral strange particle triggers is described reasonably well by the same model., Comment: 10 pages, 6 figures. Submitted to PRC

Published
2016
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20. $\rm{J}/\psi$ production at low transverse momentum in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, R., Ma, Y. G., Ma, L., Ma, G. L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Powell, C. B., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X. M., Sun, Z., Sun, Y., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, F., Wang, G., Wang, Y., Wang, J. S., Wang, H., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, Y. F., Xu, H., Xu, J., Xu, Z., Xu, N., Xu, Q. H., Yang, Y., Yang, C., Yang, S., Yang, Q., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J., Zhang, Y., Zhang, X. P., Zhang, J. B., Zhang, Z., Zhang, S., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We report on the measurement of $\rm{J}/\psi$ production in the dielectron channel at mid-rapidity (|y|<1) in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV from the STAR experiment at the Relativistic Heavy Ion Collider. The transverse momentum $p_{T}$ spectra in p+p for $p_{T}$ < 4 GeV/c and d+Au collisions for $p_{T}$ < 3 GeV/c are presented. These measurements extend the STAR coverage for $\rm{J}/\psi$ production in p+p collisions to low $p_{T}$. The $$ from the measured $\rm{J}/\psi$ invariant cross section in p+p and d+Au collisions are evaluated and compared to similar measurements at other collision energies. The nuclear modification factor for $\rm{J}/\psi$ is extracted as a function of $p_{T}$ and collision centrality in d+Au and compared to model calculations using the modified nuclear Parton Distribution Function and a final-state $\rm{J}/\psi$ nuclear absorption cross section.

Published
2016
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21. Measurement of elliptic flow of light nuclei at $\sqrt{s_{NN}}$ = 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, H. Z., Huang, X., Huang, B., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, X., Li, C., Li, Y., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, A., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, Z., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, H., Wang, J. S., Wang, Y., Wang, F., Wang, G., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, G., Xie, W., Xin, K., Xu, N., Xu, H., Xu, Z., Xu, Y. F., Xu, J., Xu, Q. H., Yang, C., Yang, Y., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J., Zhang, Z., Zhang, S., Zhang, Y., Zhang, X. P., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract

We present measurements of 2$^{nd}$ order azimuthal anisotropy ($v_{2}$) at mid-rapidity $(|y|<1.0)$ for light nuclei d, t, $^{3}$He (for $\sqrt{s_{NN}}$ = 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV) and anti-nuclei $\bar{\rm d}$ ($\sqrt{s_{NN}}$ = 200, 62.4, 39, 27, and 19.6 GeV) and $^{3}\bar{\rm He}$ ($\sqrt{s_{NN}}$ = 200 GeV) in the STAR (Solenoidal Tracker at RHIC) experiment. The $v_{2}$ for these light nuclei produced in heavy-ion collisions is compared with those for p and $\bar{\rm p}$. We observe mass ordering in nuclei $v_{2}(p_{T})$ at low transverse momenta ($p_{T}<2.0$ GeV/$c$). We also find a centrality dependence of $v_{2}$ for d and $\bar{\rm d}$. The magnitude of $v_{2}$ for t and $^{3}$He agree within statistical errors. Light-nuclei $v_{2}$ are compared with predictions from a blast wave model. Atomic mass number ($A$) scaling of light-nuclei $v_{2}(p_{T})$ seems to hold for $p_{T}/A < 1.5$ GeV/$c$. Results on light-nuclei $v_{2}$ from a transport-plus-coalescence model are consistent with the experimental measurements., Comment: 13 pages and 10 figures

Published
2016

22. Beam Energy Dependence of the Third Harmonic of Azimuthal Correlations in Au+Au Collisions at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, T., Huang, X., Huang, B., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, Y., Li, W., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, R., Ma, G. L., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, A., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Z., Sun, X. M., Sun, Y., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, F., Wang, G., Wang, J. S., Wang, H., Wang, Y., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, Y. F., Xu, Q. H., Xu, N., Xu, H., Xu, Z., Xu, J., Yang, S., Yang, Y., Yang, C., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, Y., Zhang, J., Zhang, S., Zhang, Z., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We present results from a harmonic decomposition of two-particle azimuthal correlations measured with the STAR detector in Au+Au collisions for energies ranging from $\sqrt{s_{NN}}=7.7$ GeV to 200 GeV. The third harmonic $v_3^2\{2\}=\langle \cos3(\phi_1-\phi_2)\rangle$, where $\phi_1-\phi_2$ is the angular difference in azimuth, is studied as a function of the pseudorapidity difference between particle pairs $\Delta\eta = \eta_1-\eta_2$. Non-zero {\vthree} is directly related to the previously observed large-$\Delta\eta$ narrow-$\Delta\phi$ ridge correlations and has been shown in models to be sensitive to the existence of a low viscosity Quark Gluon Plasma (QGP) phase. For sufficiently central collisions, $v_3^2\{2\}$ persist down to an energy of 7.7 GeV suggesting that QGP may be created even in these low energy collisions. In peripheral collisions at these low energies however, $v_3^2\{2\}$ is consistent with zero. When scaled by pseudorapidity density of charged particle multiplicity per participating nucleon pair, $v_3^2\{2\}$ for central collisions shows a minimum near {\snn}$=20$ GeV., Comment: 7 pages, 4 figures, for submission to Phys. Rev. Lett

Published
2016
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25. Measurement of the transverse single-spin asymmetry in $p^\uparrow+p \to W^{\pm}/Z^0$ at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, H. Z., Huang, X., Huang, B., Huang, T., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Y., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, L., Ma, R., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., McDonald, D., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, H., Wang, G., Wang, F., Wang, Y., Wang, J. S., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, J., Xu, Z., Xu, Y. F., Xu, Q. H., Xu, H., Xu, N., Yang, Q., Yang, Y., Yang, S., Yang, C., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J., Zhang, Y., Zhang, S., Zhang, J. B., Zhang, Z., Zhang, X. P., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We present the measurement of the transverse single-spin asymmetry of weak boson production in transversely polarized proton-proton collisions at $\sqrt{s} = 500~\text{GeV}$ by the STAR experiment at RHIC. The measured observable is sensitive to the Sivers function, one of the transverse momentum dependent parton distribution functions, which is predicted to have the opposite sign in proton-proton collisions from that observed in deep inelastic lepton-proton scattering. These data provide the first experimental investigation of the non-universality of the Sivers function, fundamental to our understanding of QCD., Comment: 7 pages, 4 figures, Submitted to Physical Review Letters

Published
2015
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26. Centrality dependence of identified particle elliptic flow in relativistic heavy ion collisions at sqrt(s)= 7.7--62.4 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Bai, X., Bairathi, V., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Chisman, O., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, H. Z., Huang, B., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, W., Li, C., Li, Z. M., Li, Y., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, R., Ma, L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, Z., Sun, X. M., Sun, Y., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thaeder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, F., Wang, J. S., Wang, Y., Wang, G., Wang, H., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, N., Xu, Q. H., Xu, Z., Xu, Y. F., Xu, H., Yang, C., Yang, Y., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, Z., Zhang, S., Zhang, J., Zhang, Y., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

Elliptic flow (v_2) values for identified particles at midrapidity in Au + Au collisions measured by the STAR experiment in the Beam Energy Scan at the Relativistic Heavy Ion Collider at sqrt{s_{NN}}= 7.7--62.4 GeV are presented for three centrality classes. The centrality dependence and the data at sqrt{s_{NN}}= 14.5 GeV are new. Except at the lowest beam energies we observe a similar relative v_2 baryon-meson splitting for all centrality classes which is in agreement within 15% with the number-of-constituent quark scaling. The larger v_2 for most particles relative to antiparticles, already observed for minimum bias collisions, shows a clear centrality dependence, with the largest difference for the most central collisions. Also, the results are compared with A Multiphase Transport Model and fit with a Blast Wave model., Comment: 14 pages, 12 figures, Phys. Rev. C, to be published. Data tables available at https://drupal.star.bnl.gov/STAR/publications/centrality-dependence-identified-particle-elliptic-flow-relativistic-heavy-ion-collisio

Published
2015
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27. Centrality and transverse momentum dependence of elliptic flow of multi-strange hadrons and $\phi$ meson in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Bai, X., Bairathi, V., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, C., Li, X., Li, Z. M., Li, Y., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, R., Ma, L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, J. S., Wang, Y., Wang, F., Wang, G., Wang, H., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Wu, Z. G. Xiao, Xie, W., Xin, K., Xu, Q. H., Xu, Z., Xu, H., Xu, Y. F., Xu, N., Yang, Y., Yang, C., Yang, Q., Yang, S., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, S., Zhang, J., Zhang, Y., Zhang, J. B., Zhang, Z., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract

We present high precision measurements of elliptic flow near midrapidity ($|y|<1.0$) for multi-strange hadrons and $\phi$ meson as a function of centrality and transverse momentum in Au+Au collisions at center of mass energy $\sqrt{s_{NN}}=$ 200 GeV. We observe that the transverse momentum dependence of $\phi$ and $\Omega$ $v_{2}$ is similar to that of $\pi$ and $p$, respectively, which may indicate that the heavier strange quark flows as strongly as the lighter up and down quarks. This observation constitutes a clear piece of evidence for the development of partonic collectivity in heavy-ion collisions at the top RHIC energy. Number of constituent quark scaling is found to hold within statistical uncertainty for both 0-30$\%$ and 30-80$\%$ collision centrality. There is an indication of the breakdown of previously observed mass ordering between $\phi$ and proton $v_{2}$ at low transverse momentum in the 0-30$\%$ centrality range, possibly indicating late hadronic interactions affecting the proton $v_{2}$., Comment: 7 pages and 4 figures, Accepted for publication in Physical Review Letters

Published
2015
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28. Probing Parton Dynamics of QCD Matter with $\Omega$ and $\phi$ Production

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Bairathi, V., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, Z. M., Li, Y., Li, W., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Z., Sun, X. M., Sun, Y., Sun, X., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, H., Wang, J. S., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Y. F., Xu, Q. H., Xu, H., Xu, N., Xu, Z., Yang, Y., Yang, C., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, Z., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhao, F., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We present measurements of $\Omega$ and $\phi$ production at mid-rapidity from Au+Au collisions at nucleon-nucleon center-of-mass energies $\sqrt{s_{NN}}$ = 7.7, 11.5, 19.6, 27 and 39 GeV by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Motivated by the coalescence formation mechanism for these strange hadrons, we study the ratios of $N(\Omega^{-}+\Omega^{+})/(2N(\phi))$. These ratios as a function of transverse momentum ($p_T$) fall on a consistent trend at high collision energies, but start to show deviations in peripheral collisions at $\sqrt{s_{NN}}$ = 19.6, 27 and 39 GeV, and in central collisions at 11.5 GeV in the intermediate $p_T$ region of 2.4-3.6 GeV/c. We further evaluate empirically the strange quark $p_T$ distributions at hadronization by studying the $\Omega/\phi$ ratios scaled by the number of constituent quarks. The NCQ-scaled $\Omega/\phi$ ratios show a suppression of strange quark production in central collisions at 11.5 GeV compared to $\sqrt{s_{NN}} >= 19.6$ GeV. The shapes of the presumably thermal strange quark distributions in 0-60% most central collisions at 7.7 GeV show significant deviations from those in 0-10% most central collisions at higher energies. These features suggest that there is likely a change of the underlying strange quark dynamics in the transition from quark-matter to hadronic matter at collision energies below 19.6 GeV., Comment: 7 pages, 5 figures

Published
2015
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29. Azimuthal anisotropy in U+U and Au+Au collisions at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Bairathi, V., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, Z. M., Li, Y., Li, W., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Z., Sun, X. M., Sun, Y., Sun, X., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, H., Wang, J. S., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Y. F., Xu, Q. H., Xu, H., Xu, N., Xu, Z., Yang, Y., Yang, C., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, Z., Zhang, J., Zhang, S., Zhang, X. P., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, $v_2\{2\}$ and $v_2\{4\}$, for charged hadrons from U+U collisions at $\sqrt{s_{\rm NN}}$ = 193 GeV and Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV. Nearly fully overlapping collisions are selected based on the amount of energy deposited by spectators in the STAR Zero Degree Calorimeters (ZDCs). Within this sample, the observed dependence of $v_2\{2\}$ on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. An initial-state model with gluon saturation describes the slope of $v_2\{2\}$ as a function of multiplicity in central collisions better than one based on Glauber with a two-component multiplicity model., Comment: Final paper version accepted for publication in Phys. Rev. Lett. New version includes comparisons to a constituent quark glauber model

Published
2015
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30. Observation of charge asymmetry dependence of pion elliptic flow and the possible chiral magnetic wave in heavy-ion collisions

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Bairathi, Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, Z. M., Li, X., Li, Y., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, Y. G., Ma, R., Ma, G. L., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, H., Wang, J. S., Wang, Y., Wang, F., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Q. H., Xu, N., Xu, H., Xu, Z., Xu, Y. F., Yang, Q., Yang, Y., Yang, C., Yang, S., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J., Zhang, X. P., Zhang, Z., Zhang, Y., Zhang, S., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

We present measurements of $\pi^-$ and $\pi^+$ elliptic flow, $v_2$, at midrapidity in Au+Au collisions at $\sqrt{s_{_{\rm NN}}} =$ 200, 62.4, 39, 27, 19.6, 11.5 and 7.7 GeV, as a function of event-by-event charge asymmetry, $A_{ch}$, based on data from the STAR experiment at RHIC. We find that $\pi^-$ ($\pi^+$) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at $\sqrt{s_{_{\rm NN}}} = \text{27 GeV}$ and higher. At $\sqrt{s_{_{\rm NN}}} = \text{200 GeV}$, the slope of the difference of $v_2$ between $\pi^-$ and $\pi^+$ as a function of $A_{ch}$ exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies., Comment: 6 pages, 4 figures

Published
2015
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31. Measurements of Dielectron Production in Au$+$Au Collisions at $\sqrt{s_{\rm NN}}$ = 200 GeV from the STAR Experiment

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Z. M., Li, Y., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, Y. G., Ma, G. L., Ma, L., Ma, R., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, Z., Sun, X. M., Sun, Y., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Wang, H., Wang, J. S., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Q. H., Xu, Z., Xu, H., Xu, N., Xu, Y. F., Yang, Q., Yang, Y., Yang, S., Yang, C., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, J., Zhang, Y., Zhang, J. B., Zhang, S., Zhang, Z., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report on measurements of dielectron ($e^+e^-$) production in Au$+$Au collisions at a center-of-mass energy of 200 GeV per nucleon-nucleon pair using the STAR detector at RHIC. Systematic measurements of the dielectron yield as a function of transverse momentum ($p_{\rm T}$) and collision centrality show an enhancement compared to a cocktail simulation of hadronic sources in the low invariant-mass region ($M_{ee}<$ 1 GeV/$c^2$). This enhancement cannot be reproduced by the $\rho$-meson vacuum spectral function. In minimum-bias collisions, in the invariant-mass range of 0.30 $-$ 0.76 GeV/$c^2$, integrated over the full $p_{\rm T}$ acceptance, the enhancement factor is 1.76 $\pm$ 0.06 (stat.) $\pm$ 0.26 (sys.) $\pm$ 0.29 (cocktail). The enhancement factor exhibits weak centrality and $p_{\rm T}$ dependence in STAR's accessible kinematic regions, while the excess yield in this invariant-mass region as a function of the number of participating nucleons follows a power-law shape with a power of 1.44 $\pm$ 0.10. Models that assume an in-medium broadening of the $\rho$ meson spectral function consistently describe the observed excess in these measurements. Additionally, we report on measurements of $\omega$ and $\phi$-meson production through their $e^+e^-$ decay channel. These measurements show good agreement with Tsallis Blast-Wave model predictions as well as, in the case of the $\phi$-meson, results through its $K^+K^-$ decay channel. In the intermediate invariant-mass region (1.1$

Published
2015
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32. Observation of Transverse Spin-Dependent Azimuthal Correlations of Charged Pion Pairs in $p^\uparrow+p$ at $\sqrt{s}=200$ GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., S'anchez, M. Calder'on de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Z. M., Li, Y., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, Y. G., Ma, G. L., Ma, L., Ma, R., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, Z., Sun, X. M., Sun, Y., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Wang, H., Wang, J. S., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Q. H., Xu, Z., Xu, H., Xu, N., Xu, Y. F., Yang, Q., Yang, Y., Yang, S., Yang, C., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, X. P., Zhang, J., Zhang, Y., Zhang, J. B., Zhang, S., Zhang, Z., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report the observation of transverse polarization-dependent azimuthal correlations in charged pion pair production with the STAR experiment in $p^\uparrow+p$ collisions at RHIC. These correlations directly probe quark transversity distributions. We measure signals in excess of five standard deviations at high transverse momenta, at high pseudorapidities eta>0.5, and for pair masses around the mass of the rho-meson. This is the first direct transversity measurement in p+p collisions. Comparing the results to data from lepton-nucleon scattering will test the universality of these spin-dependent quantities., Comment: 11 pages, 5 figures, 15 tables. Submitted to PRL

Published
2015
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33. The $\phi (1020)\rightarrow e^{+}e^{-}$ meson decay measured with the STAR experiment in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Bunzarov, I., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A. I., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, X., Huang, H. Z., Huang, T., Huang, B., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jentsch, A., Jia, J., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikoła, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kumar, L., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, C., Li, Y., Li, X., Li, W., Lin, T., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, R., Ma, G. L., Ma, L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Matis, H. S., McDonald, D., McKinzie, S., Meehan, K., Mei, J. C., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Niida, T., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, M. K., Sharma, A., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, D., Smirnov, N., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, Z., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A., Thäder, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Vokal, S., Voloshin, S. A., Vossen, A., Wada, M., Wang, Y., Wang, F., Wang, G., Wang, J. S., Wang, H., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xin, K., Xu, Y. F., Xu, H., Xu, Z., Xu, J., Xu, N., Xu, Q. H., Yang, Y., Yang, C., Yang, Q., Yang, S., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, S., Zhang, J., Zhang, J. B., Zhang, X. P., Zhang, Y., Zhang, Z., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report the measurement of the leptonic ($e^{+}e^{-}$) decay channel of the $\phi$(1020) meson in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV by the STAR experiment. The transverse momentum ($p_{\rm T}$) spectrum is measured for 0.1 $\le p_{\rm T} \le 2.5$ GeV/$c$ at mid-rapidity ($|y|\le1$). We obtain the $p_{\rm T}$-integrated $\phi$(1020) mass $M_{\phi}=1017.7\pm0.8 (\rm {stat.}) \pm0.9 (\rm {sys.})$ MeV/$c^{2}$ and width $\Gamma_{\phi} = 8.0\pm 2.5(\rm {stat.}) \pm 2.3(\rm {sys.}) \textrm{MeV/}c^{2}$, which are within 1.5\,$\sigma$ and 1.1\,$\sigma$ of the vacuum values, respectively. No significant difference is observed in the measured $p_{\rm T}$ spectrum, $dN/dy$, or $\left$ of the $\phi$(1020) meson between the $e^{+}e^{-}$ and hadronic ($K^{+}K^{-}$) decay channels as measured by the same experiment. The experimental results are compared to a theoretical model including medium-modified $\phi$(1020).

Published
2015

34. Long-range pseudorapidity dihadron correlations in $d$+Au collisions at $\sqrt{s_{\rm NN}}=200$ GeV

Author

Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., S'anchez, M. Calder'on de la Barca, campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Codrington, M. J. M., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, H. Z., Huang, X., Huang, B., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, W., Li, Z. M., Li, Y., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, L., Ma, R., Ma, G. L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Solanki, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B. J., Sun, Y., Sun, Z., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbaek, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, Y., Wang, F., Wang, H., Wang, J. S., Wang, G., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, Z., Xu, Q. H., Xu, N., Xu, H., Xu, Y. F., Yang, Y., Yang, C., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, X. P., Zhang, S., Zhang, J., Zhang, Z., Zhang, Y., Zhang, J. L., Zhao, F., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Dihadron angular correlations in $d$+Au collisions at $\sqrt{s_{\rm NN}}=200$ GeV are reported as a function of the measured zero-degree calorimeter neutral energy and the forward charged hadron multiplicity in the Au-beam direction. A finite correlated yield is observed at large relative pseudorapidity ($\Delta\eta$) on the near side (i.e. relative azimuth $\Delta\phi\sim0$). This correlated yield as a function of $\Delta\eta$ appears to scale with the dominant, primarily jet-related, away-side ($\Delta\phi\sim\pi$) yield. The Fourier coefficients of the $\Delta\phi$ correlation, $V_{n}=\langle\cos n\Delta\phi\rangle$, have a strong $\Delta\eta$ dependence. In addition, it is found that $V_{1}$ is approximately inversely proportional to the mid-rapidity event multiplicity, while $V_{2}$ is independent of it with similar magnitude in the forward ($d$-going) and backward (Au-going) directions., Comment: 8 pages, 4 figures

Published
2015
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35. Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+Au collisions at $\sqrt{s_{NN}} = 19.6$ and 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., S'anchez, M. Calder'on de la Barca, campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Codrington, M. J. M., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, H. Z., Huang, X., Huang, B., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Klein, S. R., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, W., Li, Z. M., Li, Y., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, L., Ma, R., Ma, G. L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Solanki, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B. J., Sun, Y., Sun, Z., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, Y., Wang, F., Wang, H., Wang, J. S., Wang, G., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, Z., Xu, Q. H., Xu, N., Xu, H., Xu, Y. F., Yang, Y., Yang, C., Yang, S., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, X. P., Zhang, S., Zhang, J., Zhang, Z., Zhang, Y., Zhang, J. L., Zhao, F., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity $|y_{ee}|<1$ in minimum-bias Au+Au collisions at $\sqrt{s_{NN}}$ = 19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened $\rho$ spectral function for $M_{ee}<1.1$ GeV/$c^{2}$. The integrated dielectron excess yield at $\sqrt{s_{NN}}$ = 19.6 GeV for $0.4

Published
2015
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36. Effect of event selection on jetlike correlation measurement in $d$+Au collisions at $\sqrt{s_{\rm{NN}}}=200$ GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., S'anchez, M. Calder'on de la Barca, campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Codrington, M. J. M., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Filip, P., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, H. Z., Huang, X., Huang, B., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Klein, S. R., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, W., Li, Z. M., Li, Y., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, L., Ma, G. L., Ma, Y. G., Ma, R., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Sharma, M. K., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B. J., Sun, Z., Sun, Y., Sun, X., Sun, X. M., Surrow, B., Svirida, D. N., Szelezniak, M. A., Takahashi, J., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbaek, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, J. S., Wang, Y., Wang, F., Wang, G., Wang, H., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, Q. H., Xu, H., Xu, N., Xu, Y. F., Xu, Z., Yan, W., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, X. P., Zhang, S., Zhang, Z., Zhang, Y., Zhang, J. L., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Dihadron correlations are analyzed in $\sqrt{s_{_{\rm NN}}} = 200$ GeV $d$+Au collisions classified by forward charged particle multiplicity and zero-degree neutral energy in the Au-beam direction. It is found that the jetlike correlated yield increases with the event multiplicity. After taking into account this dependence, the non-jet contribution on the away side is minimal, leaving little room for a back-to-back ridge in these collisions., Comment: 7 pages, 3 figures

Published
2014
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42. Energy Dependence of $K\pi$, $p\pi$, and $Kp$ Fluctuations in Au+Au Collisions from $\rm \sqrt{s_{NN}}$ = 7.7 to 200 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Codrington, M. J. M., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, H. Z., Huang, B., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Klein, S. R., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, Z. M., Li, C., Li, Y., Li, X., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, L., Ma, R., Ma, G. L., Ma, Y. G., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, S., Raniwala, R., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B. J., Sun, Z., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Tian, J., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, Y., Wang, F., Wang, J. S., Wang, H., Wang, G., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, N., Xu, H., Xu, Y. F., Xu, Q. H., Xu, Z., Yang, Y., Yang, S., Yang, C., Yang, Q., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J., Zhang, Y., Zhang, S., Zhang, X. P., Zhang, J. B., Zhang, J. L., Zhang, Z., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

A search for the quantum chromodynamics (QCD) critical point was performed by the STAR experiment at the Relativistic Heavy Ion Collider, using dynamical fluctuations of unlike particle pairs. Heavy-ion collisions were studied over a large range of collision energies with homogeneous acceptance and excellent particle identification, covering a significant range in the QCD phase diagram where a critical point may be located. Dynamical $K\pi$, $p\pi$, and $Kp$ fluctuations as measured by the STAR experiment in central 0-5\% Au+Au collisions from center-of-mass collision energies $\rm \sqrt{s_{NN}}$ = 7.7 to 200 GeV are presented. The observable $\rm \nu_{dyn}$ was used to quantify the magnitude of the dynamical fluctuations in event-by-event measurements of the $K\pi$, $p\pi$, and $Kp$ pairs. The energy dependences of these fluctuations from central 0-5\% Au+Au collisions all demonstrate a smooth evolution with collision energy., Comment: 7 pages, 3 figures

Published
2014
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43. Di-Hadron Correlations with Identified Leading Hadrons in 200 GeV Au+Au and d+Au Collisions at STAR

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandin, A. V., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cervantes, M. C., Chakaberia, I., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., di Ruzza, B., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Eppley, G., Esha, R., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Fedorisin, J., Feng, Z., Filip, P., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Hamad, A., Hamed, A., Haque, R., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, X., Huang, H. Z., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Jiang, K., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Koetke, D. D., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, W., Li, Z. M., Li, X., Li, Y., Li, C., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, Y. G., Ma, R., Ma, G. L., Ma, L., Magdy, N., Majka, R., Manion, A., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., Meehan, K., Minaev, N. G., Mioduszewski, S., Mishra, D., Mohanty, B., Mondal, M. M., Morozov, D., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V., Olvitt Jr., D., Page, B. S., Pak, R., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Peterson, A., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Skoby, M. J., Smirnov, N., Smirnov, D., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stepanov, M., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Summa, B., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, N., Szelezniak, M. A., Tang, Z., Tang, A. H., Tarnowsky, T., Tawfik, A. N., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Varma, R., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, H., Wang, J. S., Wang, Y., Wang, F., Webb, G., Webb, J. C., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z. G., Xie, W., Xin, K., Xu, Q. H., Xu, N., Xu, H., Xu, Z., Xu, Y. F., Yang, Q., Yang, Y., Yang, C., Yang, S., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J., Zhang, X. P., Zhang, Z., Zhang, Y., Zhang, S., Zhao, J., Zhong, C., Zhou, L., Zhu, X., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

The STAR collaboration presents for the first time two-dimensional di-hadron correlations with identified leading hadrons in 200 GeV central Au+Au and minimum-bias d+Au collisions to explore hadronization mechanisms in the quark gluon plasma. The enhancement of the jet-like yield for leading pions in Au+Au data with respect to the d+Au reference and the absence of such an enhancement for leading non-pions (protons and kaons) are discussed within the context of a quark recombination scenario. The correlated yield at large angles, specifically in the \emph{ridge region}, is found to be significantly higher for leading non-pions than pions. The consistencies of the constituent quark scaling, azimuthal harmonic model and a mini-jet modification model description of the data are tested, providing further constraints on hadronization.

Published
2014
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44. Isolation of Flow and Nonflow Correlations by Two- and Four-Particle Cumulant Measurements of Azimuthal Harmonics in $\sqrt{s_{_{\rm NN}}} =$ 200 GeV Au+Au Collisions

Author

Abdelwahab, N. M., Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bültmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderóndela Barca, Campbell, J. M., Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L-X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen, Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I-K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

A data-driven method was applied to measurements of Au+Au collisions at $\sqrt{s_{_{\rm NN}}} =$ 200 GeV made with the STAR detector at RHIC to isolate pseudorapidity distance $\Delta\eta$-dependent and $\Delta\eta$-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a component of the correlation that is $\Delta\eta$-independent, which is likely dominated by anisotropic flow and flow fluctuations. It was also found to be independent of $\eta$ within the measured range of pseudorapidity $|\eta|<1$. The relative flow fluctuation was found to be $34\% \pm 2\% (stat.) \pm 3\% (sys.)$ for particles of transverse momentum $p_{T}$ less than $2$ GeV/$c$. The $\Delta\eta$-dependent part may be attributed to nonflow correlations, and is found to be $5\% \pm 2\% (sys.)$ relative to the flow of the measured second harmonic cumulant at $|\Delta\eta| > 0.7$.

Published
2014
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45. Charged-to-neutral correlation at forward rapidity in Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV

Author

STAR Collaboration, Abdelwahab, N. M., Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bültmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L-X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Page, B. S., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandacz, A., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Simko, M., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen, Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I-K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

Event-by-event fluctuations of the ratio of inclusive charged to photon multiplicities at forward rapidity in Au+Au collision at $\sqrt{s_{NN}}$=200 GeV have been studied. Dominant contribution to such fluctuations is expected to come from correlated production of charged and neutral pions. We search for evidences of dynamical fluctuations of different physical origins. Observables constructed out of moments of multiplicities are used as measures of fluctuations. Mixed events and model calculations are used as baselines. Results are compared to the dynamical net-charge fluctuations measured in the same acceptance. A non-zero statistically significant signal of dynamical fluctuations is observed in excess to the model prediction when charged particles and photons are measured in the same acceptance. We find that, unlike dynamical net-charge fluctuation, charge-neutral fluctuation is not dominated by correlation due to particle decay. Results are compared to the expectations based on the generic production mechanism of pions due to isospin symmetry, for which no significant (<1%) deviation is observed., Comment: 14 pages, 6 figures

Published
2014
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46. Elliptic flow of electrons from heavy-flavor hadron decays in Au+Au collisions at $\sqrt{s_{\rm NN}} = $ 200, 62.4, and 39 GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Ajitanand, N. N., Alekseev, I., Anderson, D. M., Aoyama, R., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Ashraf, M. U., Attri, A., Averichev, G. S., Bai, X., Bairathi, V., Behera, A., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Bouchet, J., Brandenburg, J. D., Brandin, A. V., Brown, D., Bunzarov, I., Butterworth, J., Caines, H., Sanchez, M. Calderon de la Barca, Campbell, J. M., Cebra, D., Chakaberia, I., Chaloupka, P., Chang, Z., Chankova-Bunzarova, N., Chatterjee, A., Chattopadhyay, S., Chen, X., Chen, J. H., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. E., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Elsey, N., Engelage, J., Eppley, G., Esha, R., Esumi, S., Evdokimov, O., Ewigleben, J., Eyser, O., Fatemi, R., Fazio, S., Federic, P., Federicova, P., Fedorisin, J., Feng, Z., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Fulek, L., Gagliardi, C. A., Garand, D., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, S., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Horvat, S., Huang, H. Z., Huang, X., Huang, B., Huang, T., Humanic, T. J., Huo, P., Igo, G., Jacobs, W. W., Jentsch, A., Jia, J., Jiang, K., Jowzaee, S., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikola, D. P., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulathunga, N., Kumar, L., Kvapil, J., Kwasizur, J. H., Lacey, R., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., Li, X., Li, C., Li, Y., Li, W., Lidrych, J., Lin, T., Lisa, M. A., Liu, P., Liu, Y., Liu, F., Liu, H., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Luo, S., Ma, Y. G., Ma, L., Ma, R., Ma, G. L., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Meehan, K., Mei, J. C., Miller, Z. W., Minaev, N. G., Mioduszewski, S., Mishra, D., Mizuno, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nie, M., Nigmatkulov, G., Niida, T., Nogach, L. V., Nonaka, T., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Okorokov, V. A., Olvitt Jr., D., Page, B. S., Pak, R., Pandit, Y., Panebratsev, Y., Pawlik, B., Pei, H., Perkins, C., Pile, P., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Ray, R. L., Reed, R., Rehbein, M. J., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Roth, J. D., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Salur, S., Sandweiss, J., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, M. K., Sharma, A., Shen, W. Q., Shi, Z., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Song, L., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stock, R., Strikhanov, M., Stringfellow, B., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X. M., Sun, X., Surrow, B., Svirida, D. N., Tang, A. H., Tang, Z., Taranenko, A., Tarnowsky, T., Tawfik, A., Thader, J., Thomas, J. H., Timmins, A. R., Tlusty, D., Todoroki, T., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Tripathy, S. K., Trzeciak, B. A., Tsai, O. D., Ullrich, T., Underwood, D. G., Upsal, I., Van Buren, G., van Nieuwenhuizen, G., Vasiliev, A. N., Videbaek, F., Vokal, S., Voloshin, S. A., Vossen, A., Wang, G., Wang, Y., Wang, F., Webb, J. C., Webb, G., Wen, L., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y., Xiao, Z. G., Xie, W., Xie, G., Xu, J., Xu, N., Xu, Q. H., Xu, W., Xu, Y. F., Xu, Z., Yang, Y., Yang, Q., Yang, C., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, Z., Zhang, X. P., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Y., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We present measurements of elliptic flow ($v_2$) of electrons from the decays of heavy-flavor hadrons ($e_{HF}$) by the STAR experiment. For Au+Au collisions at $\sqrt{s_{\rm NN}} = $ 200 GeV we report $v_2$, for transverse momentum ($p_T$) between 0.2 and 7 GeV/c using three methods: the event plane method ($v_{2}${EP}), two-particle correlations ($v_2${2}), and four-particle correlations ($v_2${4}). For Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 62.4 and 39 GeV we report $v_2${2} for $p_T< 2$ GeV/c. $v_2${2} and $v_2${4} are non-zero at low and intermediate $p_T$ at 200 GeV, and $v_2${2} is consistent with zero at low $p_T$ at other energies. The $v_2${2} at the two lower beam energies is systematically lower than at $\sqrt{s_{\rm NN}} = $ 200 GeV for $p_T < 1$ GeV/c. This difference may suggest that charm quarks interact less strongly with the surrounding nuclear matter at those two lower energies compared to $\sqrt{s_{\rm NN}} = 200$ GeV., Comment: Version accepted by PRC

Published
2014
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47. Precision Measurement of the Longitudinal Double-spin Asymmetry for Inclusive Jet Production in Polarized Proton Collisions at $\sqrt{s}=200$ GeV

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bichsel, H., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bultmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sanchez, M. Calderon de la Barca, Campbell, J. M., Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cudd, A. B., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, Dhamija, S., di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L. -X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., LeVine, M. J., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Don, D. M. M. D. Madagodagettige, Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Pachr, M., Page, B. S., Pal, S. K., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peryt, W., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Pujahari, P. R., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Singaraju, R. N., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zawisza, Y., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report a new high-precision measurement of the mid-rapidity inclusive jet longitudinal double-spin asymmetry, $A_{LL}$, in polarized $pp$ collisions at center-of-mass energy $\sqrt{s}=200$ GeV. The STAR data place stringent constraints on polarized parton distribution functions extracted at next-to-leading order from global analyses of inclusive deep inelastic scattering (DIS), semi-inclusive DIS, and RHIC $pp$ data. The measured asymmetries provide evidence for positive gluon polarization in the Bjorken-$x$ region $x>0.05$., Comment: 7 pages, 3 figures

Published
2014
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48. Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Balewski, J., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bichsel, H., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bültmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Campbell, J. M., Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, Dhamija, S., di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L-X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., LeVine, M. J., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Don, D. M. M. D. Madagodagettige, Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Pachr, M., Page, B. S., Pal, S. K., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peryt, W., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Pujahari, P. R., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Singaraju, R. N., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen, Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I-K., Yu, N., Zawisza, Y., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We report measurements of single- and double- spin asymmetries for $W^{\pm}$ and $Z/\gamma^*$ boson production in longitudinally polarized $p+p$ collisions at $\sqrt{s} = 510$ GeV by the STAR experiment at RHIC. The asymmetries for $W^{\pm}$ were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the $W$ mass. The results are compared to theoretical predictions, constrained by recent polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range $0.05

Published
2014
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49. Observation of $D^0$ meson nuclear modifications in Au+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200 GeV

Author

Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bichsel, H., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bültmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, Dhamija, S., di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L-X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., LeVine, M. J., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Don, D. M. M. D. Madagodagettige, Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Pachr, M., Page, B. S., Pal, S. K., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peryt, W., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Pujahari, P. R., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Singaraju, R. N., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen, Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I-K., Yu, N., Zawisza, Y., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

We report the first measurement of charmed-hadron ($D^0$) production via the hadronic decay channel ($D^0\rightarrow K^- + \pi^+$) in Au+Au collisions at $\sqrt{s_{_{\mathrm{NN}}}}$ = 200\,GeV with the STAR experiment. The charm production cross-section per nucleon-nucleon collision at mid-rapidity scales with the number of binary collisions, $N_{bin}$, from $p$+$p$ to central Au+Au collisions. The $D^0$ meson yields in central Au+Au collisions are strongly suppressed compared to those in $p$+$p$ scaled by $N_{bin}$, for transverse momenta $p_{T}>3$ GeV/$c$, demonstrating significant energy loss of charm quarks in the hot and dense medium. An enhancement at intermediate $p_{T}$ is also observed. Model calculations including strong charm-medium interactions and coalescence hadronization describe our measurements., Comment: 7 pages including author list, 4 figures, submit to PRL with revised version

Published
2014
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50. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC

Author

STAR Collaboration, Adamczyk, L., Adkins, J. K., Agakishiev, G., Aggarwal, M. M., Ahammed, Z., Alekseev, I., Alford, J., Anson, C. D., Aparin, A., Arkhipkin, D., Aschenauer, E. C., Averichev, G. S., Banerjee, A., Beavis, D. R., Bellwied, R., Bhasin, A., Bhati, A. K., Bhattarai, P., Bichsel, H., Bielcik, J., Bielcikova, J., Bland, L. C., Bordyuzhin, I. G., Borowski, W., Bouchet, J., Brandin, A. V., Brovko, S. G., Bültmann, S., Bunzarov, I., Burton, T. P., Butterworth, J., Caines, H., Sánchez, M. Calderón de la Barca, Cebra, D., Cendejas, R., Cervantes, M. C., Chaloupka, P., Chang, Z., Chattopadhyay, S., Chen, H. F., Chen, J. H., Chen, L., Cheng, J., Cherney, M., Chikanian, A., Christie, W., Chwastowski, J., Codrington, M. J. M., Contin, G., Cramer, J. G., Crawford, H. J., Cui, X., Das, S., Leyva, A. Davila, De Silva, L. C., Debbe, R. R., Dedovich, T. G., Deng, J., Derevschikov, A. A., de Souza, R. Derradi, Dhamija, S., di Ruzza, B., Didenko, L., Dilks, C., Ding, F., Djawotho, P., Dong, X., Drachenberg, J. L., Draper, J. E., Du, C. M., Dunkelberger, L. E., Dunlop, J. C., Efimov, L. G., Engelage, J., Engle, K. S., Eppley, G., Eun, L., Evdokimov, O., Eyser, O., Fatemi, R., Fazio, S., Fedorisin, J., Filip, P., Finch, E., Fisyak, Y., Flores, C. E., Gagliardi, C. A., Gangadharan, D. R., Garand, D., Geurts, F., Gibson, A., Girard, M., Gliske, S., Greiner, L., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Gupta, S., Guryn, W., Haag, B., Hamed, A., Han, L-X., Haque, R., Harris, J. W., Heppelmann, S., Hirsch, A., Hoffmann, G. W., Hofman, D. J., Horvat, S., Huang, B., Huang, H. Z., Huang, X., Huck, P., Humanic, T. J., Igo, G., Jacobs, W. W., Jang, H., Judd, E. G., Kabana, S., Kalinkin, D., Kang, K., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Kesich, A., Khan, Z. H., Kikola, D. P., Kisel, I., Kisiel, A., Koetke, D. D., Kollegger, T., Konzer, J., Koralt, I., Kosarzewski, L. K., Kotchenda, L., Kraishan, A. F., Kravtsov, P., Krueger, K., Kulakov, I., Kumar, L., Kycia, R. A., Lamont, M. A. C., Landgraf, J. M., Landry, K. D., Lauret, J., Lebedev, A., Lednicky, R., Lee, J. H., LeVine, M. J., Li, C., Li, W., Li, X., Li, Y., Li, Z. M., Lisa, M. A., Liu, F., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, X., Ma, G. L., Ma, Y. G., Don, D. M. M. D. Madagodagettige, Mahapatra, D. P., Majka, R., Margetis, S., Markert, C., Masui, H., Matis, H. S., McDonald, D., McShane, T. S., Minaev, N. G., Mioduszewski, S., Mohanty, B., Mondal, M. M., Morozov, D. A., Mustafa, M. K., Nandi, B. K., Nasim, Md., Nayak, T. K., Nelson, J. M., Nigmatkulov, G., Nogach, L. V., Noh, S. Y., Novak, J., Nurushev, S. B., Odyniec, G., Ogawa, A., Oh, K., Ohlson, A., Okorokov, V., Oldag, E. W., Olvitt Jr., D. L., Pachr, M., Page, B. S., Pal, S. K., Pan, Y. X., Pandit, Y., Panebratsev, Y., Pawlak, T., Pawlik, B., Pei, H., Perkins, C., Peryt, W., Pile, P., Planinic, M., Pluta, J., Poljak, N., Poniatowska, K., Porter, J., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Pujahari, P. R., Putschke, J., Qiu, H., Quintero, A., Ramachandran, S., Raniwala, R., Raniwala, S., Ray, R. L., Riley, C. K., Ritter, H. G., Roberts, J. B., Rogachevskiy, O. V., Romero, J. L., Ross, J. F., Roy, A., Ruan, L., Rusnak, J., Rusnakova, O., Sahoo, N. R., Sahu, P. K., Sakrejda, I., Salur, S., Sandweiss, J., Sangaline, E., Sarkar, A., Schambach, J., Scharenberg, R. P., Schmah, A. M., Schmidke, W. B., Schmitz, N., Seger, J., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Sharma, B., Shen, W. Q., Shi, S. S., Shou, Q. Y., Sichtermann, E. P., Singaraju, R. N., Skoby, M. J., Smirnov, D., Smirnov, N., Solanki, D., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stevens, J. R., Stock, R., Strikhanov, M., Stringfellow, B., Sumbera, M., Sun, X., Sun, X. M., Sun, Y., Sun, Z., Surrow, B., Svirida, D. N., Symons, T. J. M., Szelezniak, M. A., Takahashi, J., Tang, A. H., Tang, Z., Tarnowsky, T., Thomas, J. H., Timmins, A. R., Tlusty, D., Tokarev, M., Trentalange, S., Tribble, R. E., Tribedy, P., Trzeciak, B. A., Tsai, O. D., Turnau, J., Ullrich, T., Underwood, D. G., Van Buren, G., van Nieuwenhuizen, G., Vandenbroucke, M., Vanfossen, Jr., J. A., Varma, R., Vasconcelos, G. M. S., Vasiliev, A. N., Vertesi, R., Videbæk, F., Viyogi, Y. P., Vokal, S., Vossen, A., Wada, M., Wang, F., Wang, G., Wang, H., Wang, J. S., Wang, X. L., Wang, Y., Webb, G., Webb, J. C., Westfall, G. D., Wieman, H., Wissink, S. W., Witt, R., Wu, Y. F., Xiao, Z., Xie, W., Xin, K., Xu, H., Xu, J., Xu, N., Xu, Q. H., Xu, Y., Xu, Z., Yan, W., Yang, C., Yang, Y., Ye, Z., Yepes, P., Yi, L., Yip, K., Yoo, I-K., Yu, N., Zawisza, Y., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J. L., Zhang, S., Zhang, X. P., Zhang, Y., Zhang, Z. P., Zhao, F., Zhao, J., Zhong, C., Zhu, X., Zhu, Y. H., Zoulkarneeva, Y., and Zyzak, M.

Subjects
Nuclear Experiment
Abstract

Local parity-odd domains are theorized to form inside a Quark-Gluon-Plasma (QGP) which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect (CME). The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this paper, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39 and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy, and tends to vanish by 7.7 GeV. The implications of these results for the CME will be discussed., Comment: 6 pages, 4 figures, accepted by Phys. Rev. Lett (more model comparisons have been added in version 2)

Published
2014
Full Text
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