4,131 results on '"Webb, G."'
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2. Action Principles and Conservation Laws for Chew-Goldberger-Low Anisotropic Plasmas
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Webb, G. M., Anco, S. C., Meleshko, S. V., and Zank, G. P.
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Physics - Plasma Physics - Abstract
The ideal CGL plasma equations, including the double adiabatic conservation laws for the parallel ($p_\parallel$) and perpendicular pressure ($p_\perp$), are investigated using a Lagrangian variational principle. An Euler-Poincar\'e variational principle is developed and the non-canonical Poisson bracket is obtained, in which the non-canonical variables consist of the mass flux ${\bf M}$, the density $\rho$, three entropy variables, $\sigma=\rho S$, $\sigma_\parallel=\rho S_\parallel$, $\sigma_\perp=\rho S_\perp$ ($S_\parallel$ and $S_\perp$ are the two scalar entropy invariants), and the magnetic induction ${\bf B}$. Conservation laws of the CGL plasma equations are derived via Noether's theorem. The Galilean group leads to conservation of energy, momentum, center of mass, and angular momentum. Cross helicity conservation arises from a fluid relabeling symmetry, and is local or nonlocal depending on whether the entropy gradients of $S_\parallel$, $S_\perp$ and $S$ are perpendicular to ${\bf B}$ or otherwise. The point Lie symmetries of the CGL system are shown to comprise the Galilean transformations and scalings., Comment: 59 pages
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- 2022
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3. Generalized Fluid Models of the Braginskii Type
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Hunana, P., Passot, T., Khomenko, E., Martinez-Gomez, D., Collados, M., Tenerani, A., Zank, G. P., Maneva, Y., Goldstein, M. L., and Webb, G. M.
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Physics - Plasma Physics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Several generalizations of the well-known fluid model of Braginskii (Rev. of Plasma Phys., 1965) are considered. We use the Landau collisional operator and the moment method of Grad. We focus on the 21-moment model that is analogous to the Braginskii model, and we also consider a 22-moment model. Both models are formulated for general multi-species plasmas with arbitrary masses and temperatures, where all the fluid moments are described by their evolution equations. The 21-moment model contains two "heat flux vectors" (3rd and 5th-order moments) and two "viscosity-tensors" (2nd and 4th-order moments). The Braginskii model is then obtained as a particular case of a one ion-electron plasma with similar temperatures, with de-coupled heat fluxes and viscosity-tensors expressed in a quasi-static approximation. We provide all the numerical values of the Braginskii model in a fully analytic form (together with the 4th and 5th-order moments). For multi-species plasmas, the model makes calculation of transport coefficients straightforward. Formulation in fluid moments (instead of Hermite moments) is also suitable for implementation into existing numerical codes. It is emphasized that it is the quasi-static approximation which makes some Braginskii coefficients divergent in a weakly-collisional regime. Importantly, we show that the heat fluxes and viscosity-tensors are coupled even in the linear approximation, and that the fully contracted (scalar) perturbations of the 4th-order moment, which are accounted for in the 22-moment model, modify the energy exchange rates. We also provide several Appendices, which can be useful as a guide for deriving the Braginskii model with the moment method of Grad., Comment: Updated version. Title change from "Braginskii-type" to "Braginskii Type" to match the published version (accepted to ApJ Supplements, 29 Jan 2022). Bookmarks included, TOC is now at the beginning, numbering in Appendix I is fixed, few typos corrected
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- 2022
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4. Godbillon-Vey Helicity and Magnetic Helicity in Magnetohydrodynamics
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Webb, G. M., Prasad, A., Anco, S. C., and Hu, Q.
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Astrophysics - Solar and Stellar Astrophysics ,Mathematical Physics - Abstract
The Godbillon-Vey invariant occurs in homology theory, and algebraic topology, when conditions for a co-dimension 1, foliation of a 3D manifold are satisfied. The magnetic Godbillon-Vey helicity invariant in magnetohydrodynamics (MHD) is a higher order helicity invariant that occurs for flows, in which the magnetic helicity density $h_m={\bf A}{\bf\cdot}{\bf B}={\bf A}{\bf\cdot}(\nabla\times{\bf A})=0$, where ${\bf A}$ is the magnetic vector potential and ${\bf B}$ is the magnetic induction. This paper obtains evolution equations for the magnetic Godbillon-Vey field $\boldsymbol{\eta}={\bf A}\times{\bf B}/|{\bf A}|^2$ and the Godbillon-Vey helicity density $h_{gv}=\boldsymbol{\eta}{\bf\cdot}(\nabla\times{\boldsymbol\eta})$ in general MHD flows in which either $h_m=0$ or $h_m\neq 0$. A conservation law for $h_{gv}$ occurs in flows for which $h_m=0$. For $h_m\neq 0$ the evolution equation for $h_{gv}$ contains a source term in which $h_m$ is coupled to $h_{gv}$ via the shear tensor of the background flow. The transport equation for $h_{gv}$ also depends on the electric field potential $\psi$, which is related to the gauge for ${\bf A}$, which takes its simplest form for the advected ${\bf A}$ gauge in which $\psi={\bf A\cdot u}$ where ${\bf u}$ is the fluid velocity. An application of the Godbillon-Vey magnetic helicity to nonlinear force-free magnetic fields used in solar physics is investigated. The possible uses of the Godbillon-Vey helicity in zero helicity flows in ideal fluid mechanics, and in zero helicity Lagrangian kinematics of three-dimensional advection are discussed., Comment: 42 pages, 10 figures, accepted for publication in Journal of Plasma Physics
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- 2019
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5. Global uncertainty in the diagnosis of neurological complications of SARS-CoV-2 infection by both neurologists and non-neurologists: An international inter-observer variability study
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Abbariao, Maritoni, Zaki, Shafiq Dexter Abou, Aleksic, Dejan, Aliling, Nicole, Rivas, Susana Arias, Artajos, Godard, Asukile, Melody, Atalar, Arife Çimen, Bae, Jong Seok, Banzrai, Chimeglkham, Bar, Michal, Barone, Valentina, Baykan, Betul, Beghi, Ettore, Berger, Thomas, Bilic, Ivica, Biller, Jose, Boskovic, Mateja, Cabreira, Verónica, Calado, Sofia, Canete, Maria Teresa, Celebisoy, Nese, Chen, Ike Leon, Chishimba, Lorraine, Chomba, Mashina, Constantino, Glenn Anthony, Cotelli, Maria Sofia, De Cauwer, Harald, Debroucker, Thomas, Orantes, Luis Del Carpio, Devaraj, Rashmi, D'Souza, Michelle, Ekizoglu, Esme, Elmali, Ayse Deniz, Fonseca, Ana Catarina, Furloni, Roberto, Gajre, Sunil, Azorin, David Garcia, Garfoot, Vanessa, Gasparic, Irena, Genç, Hamit, Glavica, Marinka, Guanaes, Luiz Gustavo, Gürsoy, Gizem, Hafiz, Nauman, Hasırcı, Buse, Helbok, Raimund, Hor, Chee Peng, Hughes, Stella, Hwang, Sungeun, Kaya, Irem Ilgezdi, Jakupi, Adi, Jamora, Roland Dominic, Kahwagi, Jamil, Kaprelyan, Ara, Kawatu, Nfwama, Kim, Manho, Kim, Hyunji, Kim, Hyun Kyung, Koffie, Desmond, Ladeira, Filipa, Lant, Suzannah, Lee, Woo-Jin, Lee, Sukyoon, Leonardo, Zerlyn, Lim, Christian Emmanuel, Lisak, Marijana, Loh, Hong Chuan, Loo, Lay Khoon, Huzjan, Arijana Lovrencic, Koh, Rosie Sue Luan Lu, Luabeya, Mesu'a Kabwa, Lugaresi, Alessandra, Macrohon, Bernadette, Majdak, Maja, Manalili, Sheryl, Manelli, Filippo, Mapoure, Yacouba Njankouo, Mascarella, Davide, Massano, João, Mataa, Mataa, Matibag, Jessica Leika, Matic-Gerodias, Alexandria, McMullen, Kate, Miranda, Miguel, Modequillo, Margaret, Shoab, Abul Kalam Mohammed, Motto, Cristina, Murphy, Sinead M., Mwendaweli, Naluca, Ng, Chen Fei, Ng, Rong Xiang, Ihsan, Mohd Khairul Nizam Nor, Nyein, Aye Myat, O'Connell, Karen, Oh, Seong-il, Ohnmar, Ohnmar, Özge, Aynur, Pajo, Azalea, Palavra, Filipe, Panteleienko, Larysa, Payne, Catherine, Pensato, Umberto, Peres, João, Peters, Steven, Polat, Burcu, Poljakovic, Zdravka, Punter, Martin Nicholas Michael, Quiles, Liz Edenberg, Ranieri, Angelo, Ratković, Marija, Renales, Maria Lina, Robles, Jose, Bedeković, Marina Roje, Rommer, Paulus, Šapina, Lidija, Sarac, Helena, Saylor, Deanna, Schmutzhard, Erich, Sharma, Anahita, Šimić, Aleksandra, Sipilä, Jussi O.T., Sokhi, Dilraj, Stagno, Mauro, Stancheva, Kristina, Stojsavljević, Marija, Subir, Ahamed, Surdhar, Sushee, Talabucon, Loreto, Jr, Tan, Hui Jan, Teoh, Sing Chiek, Vallejo, Dionis, Velioglu, Sibel K., Vukasović, Rafaela, Kit, Wong Wai, Welte, Tamara, Willekens, Barbara, Yesilot, Nilufer, Yu, Jeryl Ritzi T., Zaw, Moe Moe, Zhelyazkova, Sashka, Žitnik, Eva, Tamborska, A.A., Wood, G.K., Westenberg, E., Garcia-Azorin, D., Webb, G., Schiess, N., Netravathi, M., Baykan, B., Dervaj, R., Helbok, R., Lant, S., Özge, A., Padovani, A., Saylor, D., Schmutzhard, E., Easton, A., Lilleker, J.B., Jackson, T., Beghi, E., Ellul, M.A., Frontera, J.A., Pollak, T., Nicholson, T.R., Wood, N., Thakur, K.T., Solomon, T., Stark, R.J., Winkler, A.S., and Michael, B.D.
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- 2023
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6. An introductory guide to fluid models with anisotropic temperatures Part 2 -- Kinetic theory, Pad\'e approximants and Landau fluid closures
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Hunana, P., Tenerani, A., Zank, G. P., Goldstein, M. L., Webb, G. M., Khomenko, E., Collados, M., Cally, P. S., Adhikari, L., and Velli, M.
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Physics - Plasma Physics - Abstract
In Part 2 of our guide to collisionless fluid models, we concentrate on Landau fluid closures. These closures were pioneered by Hammett and Perkins and allow for the rigorous incorporation of collisionless Landau damping into a fluid framework. It is Landau damping that sharply separates traditional fluid models and collisionless kinetic theory, and is the main reason why the usual fluid models do not converge to the kinetic description, even in the long-wavelength low-frequency limit. We start with a brief introduction to kinetic theory, where we discuss in detail the plasma dispersion function $Z(\zeta)$, and the associated plasma response function $R(\zeta)=1+\zeta Z(\zeta)=-Z'(\zeta)/2$. We then consider a 1D (electrostatic) geometry and make a significant effort to map all possible Landau fluid closures that can be constructed at the 4th-order moment level. These closures for parallel moments have general validity from the largest astrophysical scales down to the Debye length, and we verify their validity by considering examples of the (proton and electron) Landau damping of the ion-acoustic mode, and the electron Landau damping of the Langmuir mode. We proceed by considering 1D closures at higher-order moments than the 4th-order, and as was concluded in Part 1, this is not possible without Landau fluid closures. We show that it is possible to reproduce linear Landau damping in the fluid framework to any desired precision, thus showing the convergence of the fluid and collisionless kinetic descriptions. We then consider a 3D (electromagnetic) geometry in the gyrotropic (long-wavelength low-frequency) limit and map all closures that are available at the 4th-order moment level. In the Appendix A, we provide comprehensive tables with Pad\'e approximants of $R(\zeta)$ up to the 8th-pole order, with many given in an analytic form., Comment: Improved version, now accepted to JPP Lecture Notes. Some parts were shortened and some parts were expanded. The text now contains Conclusions
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- 2019
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7. An introductory guide to fluid models with anisotropic temperatures Part 1 -- CGL description and collisionless fluid hierarchy
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Hunana, P., Tenerani, A., Zank, G. P., Khomenko, E., Goldstein, M. L., Webb, G. M., Cally, P. S., Collados, M., Velli, M., and Adhikari, L.
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Physics - Plasma Physics - Abstract
We present a detailed guide to advanced collisionless fluid models that incorporate kinetic effects into the fluid framework, and that are much closer to the collisionless kinetic description than traditional magnetohydrodynamics. Such fluid models are directly applicable to modeling turbulent evolution of a vast array of astrophysical plasmas, such as the solar corona and the solar wind, the interstellar medium, as well as accretion disks and galaxy clusters. The text can be viewed as a detailed guide to Landau fluid models and it is divided into two parts. Part 1 is dedicated to fluid models that are obtained by closing the fluid hierarchy with simple (non Landau fluid) closures. Part 2 is dedicated to Landau fluid closures. Here in Part 1, we discuss the CGL fluid model in great detail, together with fluid models that contain dispersive effects introduced by the Hall term and by the finite Larmor radius (FLR) corrections to the pressure tensor. We consider dispersive effects introduced by the non-gyrotropic heat flux vectors. We investigate the parallel and oblique firehose instability, and show that the non-gyrotropic heat flux strongly influences the maximum growth rate of these instabilities. Furthermore, we discuss fluid models that contain evolution equations for the gyrotropic heat flux fluctuations and that are closed at the 4th-moment level by prescribing a specific form for the distribution function. For the bi-Maxwellian distribution, such a closure is known as the "normal" closure. We also discuss a fluid closure for the bi-kappa distribution. Finally, by considering one-dimensional Maxwellian fluid closures at higher-order moments, we show that such fluid models are always unstable. The last possible non Landau fluid closure is therefore the "normal" closure, and beyond the 4th-order moment, Landau fluid closures are required., Comment: Improved version, accepted to JPP Lecture Notes. Some parts were shortened and some parts were expanded. The text now contains Conclusions
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- 2019
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8. New closures for more precise modeling of Landau damping in the fluid framework
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Hunana, P., Zank, G. P., Laurenza, M., Tenerani, A., Webb, G. M., Goldstein, M. L., Velli, M., and Adhikari, L.
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Physics - Plasma Physics - Abstract
Incorporation of kinetic effects such as Landau damping into a fluid framework was pioneered by Hammett and Perkins PRL 1990, by obtaining closures of the fluid hierarchy, where the gyrotropic heat flux fluctuations or the deviation of the 4th-order gyrotropic fluid moment, are expressed through lower-order fluid moments. To obtain a closure of a fluid model expanded around a bi-Maxwellian distribution function, the usual plasma dispersion function $Z(\zeta)$ that appears in kinetic theory or the associated plasma response function $R(\zeta)=1 + \zeta Z(\zeta)$, have to be approximated with a suitable Pad\'e approximant in such a way, that the closure is valid for all $\zeta$ values. Such closures are rare, and the original closures of Hammett and Perkins are often employed. Here we present a complete mapping of all plausible Landau fluid closures that can be constructed at the level of 4th-order moments in the gyrotropic limit and we identify the most precise closures. Furthermore, by considering 1D closures at higher-order moments, we show that it is possible to reproduce linear Landau damping in the fluid framework to any desired precision, thus showing convergence of the fluid and collisionless kinetic descriptions., Comment: Phys. Rev. Lett
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- 2018
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9. On a Vector-host Epidemic Model with Spatial Structure
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Magal, Pierre, Webb, G. F., and Wu, Yixiang
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Mathematics - Analysis of PDEs ,35B40, 35P05, 35Q92 - Abstract
In this paper, we study a reaction-diffusion vector-host epidemic model. We define the basic reproduction number $R_0$ and show that $R_0$ is a threshold parameter: if $R_0\le 1$ the disease free steady state is globally stable; if $R_0>1$ the model has a unique globally stable positive steady state. We then write $R_0$ as the spectral radius of the product of one multiplicative operator $R(x)$ and two compact operators with spectral radius equalling one. Here $R(x)$ corresponds to the basic reproduction number of the model without diffusion and is thus called local basic reproduction number. We study the relationship between $R_0$ and $R(x)$ as the diffusion rates vary.
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- 2018
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10. Azimuthal anisotropy in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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., Dedovich, T. G., Deng, J., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Herrmann, N., Hirsch, A., Horvat, S., Huang, X., Huang, H. Z., Huang, T., Huang, B., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, C., Li, X., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, F., Liu, P., Liu, Y., Liu, H., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mayes, D., 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., Nemes, D. B., 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Poskanzer, A. M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, X., Sun, Y., Sun, X. M., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., 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., Tu, B., 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, F., 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., Xu, Q. H., Xu, Y. F., Xu, J., Xu, N., Xu, Z., Yang, C., Yang, S., Yang, Q., Yang, Y., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J., Zhang, S., Zhang, L., Zhang, X. P., Zhang, Z., Zhang, Y., Zhao, J., Zhong, C., Zhou, C., Zhou, L., Zhu, X., Zhu, Z., and Zyzak, M.
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Nuclear Experiment - Abstract
The azimuthal anisotropic flow of identified and unidentified charged particles has been systematically studied in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV for harmonics $n=$ 1-4 in the pseudorapidity range $|\eta|<1$. The directed flow in Cu+Au collisions is compared with the rapidity-odd and, for the first time, the rapidity-even components of charged particle directed flow in Au+Au collisions at $\sqrt{s_{_{NN}}}$ = 200~GeV. The slope of the directed flow pseudorapidity dependence in Cu+Au collisions is found to be similar to that in Au+Au collisions, with the intercept shifted toward positive $\eta$ values, i.e., the Cu-going direction. The mean transverse momentum projected onto the spectator plane, $\langle p_x\rangle$, in Cu+Au collision also exhibits approximately linear dependence on $\eta$ with the intercept at about $\eta\approx-0.4$, closer to the rapidity of the Cu+Au system center-of-mass. The observed dependencies find natural explanation in a picture of the directed flow originating partly due the "tilted source" and partly due to the rapidity dependent asymmetry in the initial density distribution. Charge-dependence of the $\langle p_x\rangle$ was also observed in Cu+Au collisions, indicating an effect of the initial electric field created by charge difference of the spectator protons in two colliding nuclei. The rapidity-even component of directed flow in Au+Au collisions is close to that in Pb+Pb collisions at $\sqrt{s_{_{NN}}}$ = 2.76 TeV, indicating a similar magnitude of dipole-like fluctuations in the initial-state density distribution. Higher harmonic flow in Cu+Au collisions exhibits similar trends to those observed in Au+Au and Pb+Pb collisions and is qualitatively reproduced by a viscous hydrodynamic model and a multi-phase transport model. For all harmonics with $n\ge2$ we observe an approximate scaling of $v_n$ with the number of constituent quarks., Comment: 20 pages, 19 figures, Accepted for publication in Phys. Rev. C
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- 2017
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11. A survey of emerging technologies for the future of routine visual inspection of bridge structures
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Nepomuceno, D.T., primary, Vardanega, P.J., additional, Tryfonas, T., additional, Pregnolato, M., additional, Bennetts, J., additional, and Webb, G., additional
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- 2022
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12. SHM deployments for two bridge structures: Assessing potential value
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Nepomuceno, D.T., primary, Vardanega, P.J., additional, Tryfonas, T., additional, Pregnolato, M., additional, Bennetts, J., additional, Webb, G., additional, Foster, A., additional, Augustine, L., additional, and Holland, M., additional
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- 2022
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13. Transverse spin-dependent azimuthal correlations of charged pion pairs measured in p$^\uparrow$+p collisions at $\sqrt{s}$ = 500 GeV
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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., Dedovich, T. G., Deng, J., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Herrmann, N., Hirsch, A., Horvat, S., Huang, X., Huang, H. Z., Huang, T., Huang, B., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, C., Li, X., Li, Y., Lidrych, J., Lin, T., Lisa, M. A., Liu, F., Liu, P., Liu, Y., Liu, H., Ljubicic, T., Llope, W. J., Lomnitz, M., Longacre, R. S., Luo, S., Luo, X., Ma, G. L., Ma, R., Ma, Y. G., Ma, L., Magdy, N., Majka, R., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mayes, D., 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., Nemes, D. B., 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, X., Sun, Y., Sun, X. M., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., 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., Tu, B., 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, F., 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., Xu, Q. H., Xu, Y. F., Xu, J., Xu, N., Xu, Z., Yang, C., Yang, S., Yang, Q., Yang, Y., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, J., Zhang, S., Zhang, L., Zhang, X. P., Zhang, Z., Zhang, Y., Zhao, J., Zhong, C., Zhou, C., Zhou, L., Zhu, X., Zhu, Z., and Zyzak, M.
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High Energy Physics - Experiment ,Nuclear Experiment - Abstract
The transversity distribution, which describes transversely polarized quarks in transversely polarized nucleons, is a fundamental component of the spin structure of the nucleon, and is only loosely constrained by global fits to existing semi-inclusive deep inelastic scattering (SIDIS) data. In transversely polarized $p^\uparrow+p$ collisions it can be accessed using transverse polarization dependent fragmentation functions which give rise to azimuthal correlations between the polarization of the struck parton and the final state scalar mesons. This letter reports on spin dependent di-hadron correlations measured by the STAR experiment. The new dataset corresponds to 25 pb$^{-1}$ integrated luminosity of $p^\uparrow+p$ collisions at $\sqrt{s}=500$ GeV, an increase of more than a factor of ten compared to our previous measurement at $\sqrt{s}=200$ GeV. Non-zero asymmetries sensitive to transversity are observed at a $Q^2$ of several hundred GeV and are found to be consistent with the former measurement and a model calculation. %we observe consistent with the former measurement are observed.} We expect that these data will enable an extraction of transversity with comparable precision to current SIDIS datasets but at much higher momentum transfers where subleading effects are suppressed., Comment: 20 pages, 7 figures, 5 tables, submitted to PLB
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- 2017
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14. Collision Energy Dependence of Moments of Net-Kaon Multiplicity Distributions at RHIC
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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., Dedovich, T. G., Deng, J., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Herrmann, N., Hirsch, A., Horvat, S., Huang, B., Huang, T., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, W., Li, Y., Li, C., Lidrych, J., Lin, T., Lisa, M. A., Liu, F., Liu, P., Liu, Y., Liu, H., 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., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mayes, D., 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., Nemes, D. B., 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Sarkar, A., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X., Sun, X. M., 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, 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., Xu, Y. F., Xu, J., Xu, Q. H., Xu, N., Xu, Z., 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., Zhang, S., Zhang, Y., Zhang, X. P., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.
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Nuclear Experiment ,High Energy Physics - Experiment ,High Energy Physics - Phenomenology ,Nuclear Theory - Abstract
Fluctuations of conserved quantities such as baryon number, charge, and strangeness are sensitive to the correlation length of the hot and dense matter created in relativistic heavy-ion collisions and can be used to search for the QCD critical point. We report the first measurements of the moments of net-kaon multiplicity distributions in Au+Au collisions at $\sqrt{s_{\rm NN}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV. The collision centrality and energy dependence of the mean ($M$), variance ($\sigma^2$), skewness ($S$), and kurtosis ($\kappa$) for net-kaon multiplicity distributions as well as the ratio $\sigma^2/M$ and the products $S\sigma$ and $\kappa\sigma^2$ are presented. Comparisons are made with Poisson and negative binomial baseline calculations as well as with UrQMD, a transport model (UrQMD) that does not include effects from the QCD critical point. Within current uncertainties, the net-kaon cumulant ratios appear to be monotonic as a function of collision energy., Comment: 12 pages, 11 figures
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- 2017
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15. Beam-Energy Dependence of Directed Flow of $\Lambda$, $\bar{\Lambda}$, $K^\pm$, $K^0_s$ and $\phi$ in Au+Au Collisions
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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., Dedovich, T. G., Deng, J., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Herrmann, N., Hirsch, A., Horvat, S., Huang, B., Huang, T., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, W., Li, Y., Li, C., Lidrych, J., Lin, T., Lisa, M. A., Liu, F., Liu, P., Liu, Y., Liu, H., 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., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mayes, D., 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., Nemes, D. B., 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X., Sun, X. M., 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, 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., Xu, Y. F., Xu, J., Xu, Q. H., Xu, N., Xu, Z., 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., Zhang, S., Zhang, Y., Zhang, X. P., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.
- Subjects
High Energy Physics - Experiment ,Nuclear Experiment - Abstract
Rapidity-odd directed flow measurements at midrapidity are presented for $\Lambda$, $\bar{\Lambda}$, $K^\pm$, $K^0_s$ and $\phi$ at $\sqrt{s_{NN}} =$ 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4 and 200 GeV in Au+Au collisions recorded by the STAR detector at the Relativistic Heavy Ion Collider. These measurements greatly expand the scope of data available to constrain models with differing prescriptions for the equation of state of quantum chromodynamics. Results show good sensitivity for testing a picture where flow is assumed to be imposed before hadron formation and the observed particles are assumed to form via coalescence of constituent quarks. The pattern of departure from a coalescence-inspired sum-rule can be a valuable new tool for probing the collision dynamics., Comment: 7 pages, 3 figures, STAR collaboration. Revised version accepted by PRL
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- 2017
- Full Text
- View/download PDF
16. Azimuthal transverse single-spin asymmetries of inclusive jets and charged pions within jets from polarized-proton collisions at $\sqrt{s} = 500$ GeV
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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., Dedovich, T. G., Deng, J., Deppner, I. M., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Herrmann, N., Hirsch, A., Horvat, S., Huang, B., Huang, T., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, W., Li, Y., Li, C., Lidrych, J., Lin, T., Lisa, M. A., Liu, F., Liu, P., Liu, Y., Liu, H., 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., Mallick, D., Margetis, S., Markert, C., Matis, H. S., Mayes, D., 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., Nemes, D. B., 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., Shen, W. Q., Shi, S. S., Shi, Z., Shou, Q. Y., Sichtermann, E. P., Sikora, R., Simko, M., Singha, S., Skoby, M. J., Smirnov, N., Smirnov, D., Solyst, W., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Stewart, D. J., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X., Sun, X. M., 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, 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., Xu, Y. F., Xu, J., Xu, Q. H., Xu, N., Xu, Z., 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., Zhang, S., Zhang, Y., Zhang, X. P., Zhang, J. B., Zhao, J., Zhong, C., Zhou, L., Zhou, C., Zhu, X., Zhu, Z., and Zyzak, M.
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High Energy Physics - Experiment ,Nuclear Experiment - Abstract
We report the first measurements of transverse single-spin asymmetries for inclusive jet and jet + $\pi^{\pm}$ production at midrapidity from transversely polarized proton-proton collisions at $\sqrt{s} = 500$ GeV. The data were collected in 2011 with the STAR detector sampled from 23 pb$^{-1}$ integrated luminosity with an average beam polarization of 53%. Asymmetries are reported for jets with transverse momenta $6 < p_{T, jet} < 55$ GeV/c and pseudorapidity $|\eta| < 1$. Presented are measurements of the inclusive-jet azimuthal transverse single-spin asymmetry, sensitive to twist-3 initial-state quark-gluon correlators; the Collins asymmetry, sensitive to quark transversity coupled to the polarized Collins fragmentation function; and the first measurement of the "Collins-like" asymmetry, sensitive to linearly polarized gluons. Within the present statistical precision, inclusive-jet and Collins-like asymmetries are small, with the latter allowing the first experimental constraints on gluon linear polarization in a polarized proton. At higher values of jet transverse momenta, we observe the first non-zero Collins asymmetries in polarized-proton collisions, with a statistical significance of greater than $5\sigma$. The results span a range of x similar to results from SIDIS but at much higher $Q^{2}$. The Collins results enable tests of universality and factorization-breaking in the transverse momentum-dependent formulation of perturbative quantum chromodynamics., Comment: 19 pages, 13 figures; Changes for version 2, as accepted by PRD: additional figure (new Fig. 2) comparing kinematic range of these data to existing DIS data, minor text updates for clarity
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- 2017
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17. Beam Energy Dependence of Jet-Quenching Effects in Au+Au Collisions at $\sqrt{s_{_{ \mathrm{NN}}}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV
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STAR Collaboration, Adamczyk, L., Adams, J. R., 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., Barish, K., 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., Bryslawskyj, J., 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, J. H., Chen, X., Cheng, J., Cherney, M., Christie, W., Contin, G., Crawford, H. J., Das, S., Dedovich, T. G., Deng, J., Derevschikov, A. A., Didenko, L., Dilks, C., Dong, X., Drachenberg, J. L., Draper, J. 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., Geurts, F., Gibson, A., Girard, M., Grosnick, D., Gunarathne, D. S., Guo, Y., Gupta, A., Guryn, W., Hamad, A. I., Hamed, A., Harlenderova, A., Harris, J. W., He, L., Heppelmann, S., Hirsch, A., Horvat, S., Huang, X., Huang, B., Huang, T., 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., Kapukchyan, D., Kauder, K., Ke, H. W., Keane, D., Kechechyan, A., Khan, Z., Kikoła, D. P., Kim, C., Kisel, I., Kisiel, A., Kochenda, L., Kocmanek, M., Kollegger, T., Kosarzewski, L. K., Kraishan, A. F., Krauth, L., 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, C., Li, Y., Li, X., 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, X., Luo, S., Ma, Y. G., Ma, L., Ma, G. 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., Pluta, J., Poniatowska, K., Porter, J., Posik, M., Pruthi, N. K., Przybycien, M., Putschke, J., 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., Sangaline, E., Saur, M., Schambach, J., Schmah, A. M., Schmidke, W. B., Schmitz, N., Schweid, B. R., Seger, J., Sergeeva, M., Seto, R., Seyboth, P., Shah, N., Shahaliev, E., Shanmuganathan, P. V., Shao, M., 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., Sorensen, P., Spinka, H. M., Srivastava, B., Stanislaus, T. D. S., Strikhanov, M., Stringfellow, B., Suaide, A. A. P., Sugiura, T., Sumbera, M., Summa, B., Sun, Y., Sun, X., Sun, X. M., Surrow, B., Svirida, D. N., Tang, Z., Tang, A. H., 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, Y., Wang, G., Wang, F., 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., Xu, Q. H., Xu, N., Xu, Z., Xu, J., Xu, Y. F., Yang, Q., Yang, C., Yang, Y., Yang, S., Ye, Z., Yi, L., Yip, K., Yoo, I. -K., Yu, N., Zbroszczyk, H., Zha, W., Zhang, J. B., Zhang, S., Zhang, J., Zhang, Z., Zhang, Y., Zhang, X. P., Zhao, J., Zhong, C., Zhou, C., Zhou, L., Zhu, X., Zhu, Z., and Zyzak, M.
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Nuclear Experiment ,High Energy Physics - Experiment - Abstract
We report measurements of the nuclear modification factor, $R_{ \mathrm{CP}}$, for charged hadrons as well as identified $\pi^{+(-)}$, $K^{+(-)}$, and $p(\overline{p})$ for Au+Au collision energies of $\sqrt{s_{_{ \mathrm{NN}}}}$ = 7.7, 11.5, 14.5, 19.6, 27, 39, and 62.4 GeV. We observe a clear high-$p_{\mathrm{T}}$ net suppression in central collisions at 62.4 GeV for charged hadrons which evolves smoothly to a large net enhancement at lower energies. This trend is driven by the evolution of the pion spectra, but is also very similar for the kaon spectra. While the magnitude of the proton $R_{ \mathrm{CP}}$ at high $p_{\mathrm{T}}$ does depend on collision energy, neither the proton nor the anti-proton $R_{ \mathrm{CP}}$ at high $p_{\mathrm{T}}$ exhibit net suppression at any energy. A study of how the binary collision scaled high-$p_{\mathrm{T}}$ yield evolves with centrality reveals a non-monotonic shape that is consistent with the idea that jet-quenching is increasing faster than the combined phenomena that lead to enhancement., Comment: 3 figures
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- 2017
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18. Coherent diffractive photoproduction of $\rho^{0}$ mesons on gold nuclei at RHIC
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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
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- 2017
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19. Measurements of jet quenching with semi-inclusive hadron+jet distributions in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
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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., Emov, 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., Homann, G. W., Horvat, S., Huang, T., Huang, B., Huang, X., Huang, H. Z., Humanic, T. J., Huo, P., Igo, G., Jacobs, P. M., 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., la, D. P. Kiko, 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., Tawk, 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., Videbk, 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.
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Nuclear Experiment ,High Energy Physics - Experiment - Abstract
The STAR Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum hadron trigger, in central and peripheral Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. Charged jets are reconstructed with the anti-kT algorithm for jet radii R between 0.2 and 0.5 and with low infrared cutoff of track constituents ($p_T>0.2$ GeV/c). A novel mixed-event technique is used to correct the large uncorrelated background present in heavy ion collisions. Corrected recoil jet distributions are reported at mid-rapidity, for charged-jet transverse momentum $p_T^\mathrm{jet,ch}<30$ GeV/c. Comparison is made to similar measurements for Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV, to calculations for p+p collisions at $\sqrt{s}$ = 200 GeV based on the PYTHIA Monte Carlo generator and on a Next-to-Leading Order perturbative QCD approach, and to theoretical calculations incorporating jet quenching. The recoil jet yield is suppressed in central relative to peripheral collisions, with the magnitude of the suppression corresponding to medium-induced charged energy transport out of the jet cone of $2.8\pm0.2\mathrm{(stat)}\pm1.5\mathrm{(sys)}$ GeV/c, for $10
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- 2017
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20. Bulk Properties of the Medium Produced in Relativistic Heavy-Ion Collisions from the Beam Energy Scan Program
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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
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- 2017
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21. Constraining the initial conditions and temperature dependent transport with three-particle correlations in Au+Au collisions
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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
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- 2017
- Full Text
- View/download PDF
22. Harmonic decomposition of three-particle azimuthal correlations at RHIC
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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.
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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
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- 2017
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23. Measurement of $D^0$ azimuthal anisotropy at mid-rapidity in Au+Au collisions at \sNN = 200\,GeV
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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.
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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
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- 2017
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24. On Magnetohydrodynamic Gauge Field Theory
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Webb, G. M. and Anco, S. C.
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Physics - Plasma Physics - Abstract
Clebsch potential gauge field theory for magnetohydrodynamics is developed based in part on the theory of Calkin (1963). It is shown how the polarization vector ${\bf P}$ in Calkin's approach, naturally arises from the Lagrange multiplier constraint equation for Faraday's equation for the magnetic induction ${\bf B}$, or alternatively from the magnetic vector potential form of Faraday's equation. Gauss's equation, (divergence of ${\bf B}$ is zero), is incorporated in the variational principle by means of a Lagrange multiplier constraint. Noether's theorem, coupled with the gauge symmetries is used to derive the conservation laws for (a)\ magnetic helicity (b)\ cross helicity, (c) fluid helicity for non-magnetized fluids, and (d) a class of conservation laws associated with curl and divergence equations, which applies to Faraday's equation and Gauss's equation. The magnetic helicity conservation law is due to a gauge symmetry in MHD and not due to a fluid relabelling symmetry. The analysis is carried out for the general case of a non-barotropic gas, in which the gas pressure and internal energy density depend on both the entropy $S$ and the gas density $\rho$. The cross helicity and fluid helicity conservation laws in the non-barotropic case, are nonlocal conservation laws, that reduce to local conservation laws for the case of a barotropic gas. The connections between gauge symmetries, Clebsch potentials and Casimirs are developed. It is shown that the gauge symmetry functionals in the work of Henyey (1982) satisfy the Casimir determining equations., Comment: 38 pages
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- 2017
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25. Overcoming the collaborative challenge: commitment as a super-ordinate enabler of value co-creation
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Fawcett, Stanley E., Fawcett, Amydee M., Knemeyer, August Michael, Brockhaus, Sebastian, and Webb, G. Scott
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- 2021
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26. Measurement of the cross section and longitudinal double-spin asymmetry for di-jet production in polarized $pp$ collisions at $\sqrt{s}$ = 200 GeV
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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.
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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
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- 2016
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27. Di-Jet Imbalance Measurements at $\sqrt{s_{NN}} = 200$ GeV at STAR
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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
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- 2016
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28. Upsilon production in U+U collisions at 193 GeV with the STAR experiment
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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
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- 2016
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29. Charge-dependent directed flow in Cu+Au collisions at $\sqrt{s_{_{NN}}}$ = 200 GeV
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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
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- 2016
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30. Energy dependence of $J/\psi$ production in Au+Au collisions at $\sqrt{s_{NN}} =$ 39, 62.4 and 200 GeV
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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.
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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.
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- 2016
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31. An Outbreak Vector-host Epidemic Model with Spatial Structure: The 2015 Zika Outbreak in Rio de Janeiro
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Fitzgibbon, W., Morgan, J., and Webb, G.
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Quantitative Biology - Populations and Evolution - Abstract
Background: A deterministic model is developed for the spatial spread of an epidemic disease in a geographical setting. The disease is borne by vectors to susceptible hosts through criss-cross dynamics. The model is focused on an epidemic outbreak that initiates from a small number of cases in a small sub-region of the geographical setting. Methods: Partial differential equations are formulated to describe the interaction of the model compartments. Results: The partial differential equations of the model are analyzed and proven to be well-posed. The epidemic outcomes of the model are correlated to the spatially dependent parameters and initial conditions of the model. Conclusions: A version of the model is applied to the 2015-2016 Zika outbreak in the Rio de Janeiro Municipality in Brazil.
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- 2016
32. 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
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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.
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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
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- 2016
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33. $\rm{J}/\psi$ production at low transverse momentum in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV
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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 $
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- 2016
- Full Text
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34. 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
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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.
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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
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- 2016
35. Vorticity and Symplecticity in Multi-Symplectic Lagrangian Gas Dynamics
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Webb, G. M. and Anco, S. C.
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Mathematical Physics ,74A99, 76N99 - Abstract
The Lagrangian, multi-dimensional, ideal, compressible gasdynamic equations are written in a multi-symplectic form, in which the Lagrangian fluid labels, $m^i$ (the Lagrangian mass coordinates) and time $t$ are the independent variables, and in which the Eulerian position of the fluid element ${\bf x}={\bf x}({\bf m},t)$ and the entropy $S=S({\bf m},t)$ are the dependent variables. Constraints in the variational principle are incorporated by means of Lagrange multipliers. The constraints are: the entropy advection equation $S_t=0$, the Lagrangian map equation ${\bf x}_t={\bf u}$ where ${\bf u}$ is the fluid velocity, and the mass continuity equation which has the form $J=\tau$ where $J=\det(x_{ij})$ is the Jacobian of the Lagrangian map in which $x_{ij}=\partial x^i/\partial m^j$ and $\tau=1/\rho$ is the specific volume of the gas. The internal energy per unit volume of the gas $\varepsilon=\varepsilon(\rho,S)$ corresponds to a non-barotropic gas. The Lagrangian is used to define multi-momenta, and to develop de-Donder Weyl Hamiltonian equations. The de Donder Weyl equations are cast in a multi-symplectic form. The pullback conservation laws and the symplecticity conservation laws are obtained. One class of symplecticity conservation laws give rise to vorticity and potential vorticity type conservation laws, and another class of symplecticity laws are related to derivatives of the Lagrangian energy conservation law with respect to the Lagrangian mass coordinates $m^i$. We show that the vorticity-symplecticity laws can be derived by a Lie dragging method, and also by using Noether's second theorem and a fluid relabelling symmetry which is a divergence symmetry of the action. We obtain the Cartan-Poincar\'e form describing the equations and we discuss a set of differential forms representing the equation system., Comment: 48 pages, 0 figures
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- 2016
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36. Beam Energy Dependence of the Third Harmonic of Azimuthal Correlations in Au+Au Collisions at RHIC
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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.
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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
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- 2016
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37. Context-Based Masking for Spontaneous Venous Pulsations Detection
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Liu, T, Yue, L, Webb, G, Wang, D, Sheng, H, Yu, X, Li, X, Golzan, M, Liu, T, Yue, L, Webb, G, Wang, D, Sheng, H, Yu, X, Li, X, and Golzan, M
- Abstract
Spontaneous retinal venous pulsations (SVP) serve as vital dynamic biomarkers, representing rhythmic changes of the central retinal vein observed at the optic disc region (ODR) within an eye. SVPs serve as vital dynamic biomarkers, representing rhythmic changes of the central retinal vein observed at the optic disc region (ODR) within an eye. In light of their crucial clinical role, automatic detection of SVPs from fundus videos has become an area of burgeoning research. However, the inherent eye movements and the variability in retinal video quality present significant challenges to direct SVP detection via existing deep learning models. In response, we devise a spatio-temporal context-based masking approach (STC Masking), exploiting the spatiotemporal characteristics of SVPs to enhance their detection in retinal videos. We first apply a spatio-temporal mask to clip the video into an ODR-focused video tube. Diverging from conventional masking with gray or black blocks, we then employ a context masking method which using the original pixel values from video frames as the mask fill-in. The context mask map temporally transforms the dynamic video tubes into static tubes, thus changing the pulsation status of SVPs. Correspondingly, we adjust the SVP video labels based on the changing extent of masked regions to avoid ambiguity in data labelling. This innovative strategy provides more vivid videos which are similar to unmasked videos pixel-wise but having contrast semantics in SVP presenting regions. This enables network to capture the most discriminating regions through spatio-temporal variations, allowing explicit detection on SVP existence in the video. Our experiments illustrate the efficacy of our STC masking strategy, outperforming baseline methods. This work, thereby, underscores the potential of grid context-based masking for more accurate SVP detection in retinal video analysis.
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- 2024
38. No Token Left Behind: Efficient Vision Transformer via Dynamic Token Idling
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Liu, T, Yue, L, Webb, G, Wang, D, Xu, X, Li, C, Chen, Y, Chang, X, Liu, J, Wang, S, Liu, T, Yue, L, Webb, G, Wang, D, Xu, X, Li, C, Chen, Y, Chang, X, Liu, J, and Wang, S
- Abstract
Vision Transformers (ViTs) have demonstrated outstanding performance in computer vision tasks, yet their high computational complexity prevents their deployment in computing resource-constrained environments. Various token pruning techniques have been introduced to alleviate the high computational burden of ViTs by dynamically dropping image tokens. However, some undesirable pruning at early stages may result in permanent loss of image information in subsequent layers, consequently hindering model performance. To address this problem, we propose IdleViT, a dynamic token-idle-based method that achieves an excellent trade-off between performance and efficiency. Specifically, in each layer, IdleViT selects a subset of the image tokens to participate in computations while keeping the rest of the tokens idle and directly passing them to this layer’s output. By allowing the idle tokens to be re-selected in the following layers, IdleViT mitigates the negative impact of improper pruning in the early stages. Furthermore, inspired by the normalized graph cut, we devise a token cut loss on the attention map as regularization to improve IdleViT’s token selection ability. Our method is simple yet effective and can be extended to pyramid ViTs since no token is completely dropped. Extensive experimental results on various ViT architectures have shown that IdleViT can diminish the complexity of pretrained ViTs by up to 33% with no more than 0.2% accuracy decrease on ImageNet, after finetuning for only 30 epochs. Notably, when the keep ratio is 0.5, IdleViT outperforms the state-of-the-art EViT on DeiT-S by 0.5% higher accuracy and even faster inference speed. The source code is available in the supplementary material.
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- 2024
39. Enhance Reading Comprehension from EEG-Based Brain-Computer Interface
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Liu, T, Yue, L, Webb, G, Wang, D, Liu, X, Cao, Z, Liu, T, Yue, L, Webb, G, Wang, D, Liu, X, and Cao, Z
- Abstract
Electroencephalography (EEG)-based brain-computer interfaces (BCIs) have emerged as a valuable technology for decoding human cognitive processes, including reading attention and cognitive loads. While previous studies have explored eye fixations during word recognition, the intricacies of brain dynamics involved in sentence comprehension in the temporal or spectral domains still need to be discovered. Addressing this gap is crucial for enhancing learning processes; thus, in this study, we propose the first acquisition and recognition of event-related potentials and spectral perturbations using channel and independent component analysis, based on sentence-level simultaneous EEG and eye-tracking recorded from human natural reading tasks. Our results showed peaks of brain activation evoked at around 162 ms (approaching 200 ms) after the stimulus (starting to read each sentence) in the occipital area, indicating the onset timing of human retrieving lexical and semantic visual information processing. Approximately 200 ms occipital area presented increased alpha power and decreased beta and gamma power, relative to the baseline. Our results implied that most semantic-perception responses occurred around 200 ms in alpha, beta and gamma bands to facilitate human reading representation. The implications of our study underscore the significance of EEG-based BCI applications in reading tasks, serving as a potential catalyst for improving cognitive attention and comprehension in end-user reading and learning experiences. By retrieving the intricate cognitive mechanisms underlying sentence comprehension, we pave the way for developing brain-computer learning strategies to optimise reading instruction and support a diverse range of users.
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- 2024
40. Detecting Stress from Multivariate Time Series Data Using Topological Data Analysis
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Liu, T, Yue, L, Webb, G, Wang, D, Tran, HV, McGregor, C, Kennedy, PJ, Liu, T, Yue, L, Webb, G, Wang, D, Tran, HV, McGregor, C, and Kennedy, PJ
- Abstract
Stress can have dangerous effects to human mental and physical health. Statistics, machine learning and novel data analytics approaches have been used to detect stress from physiological time series data. However such data is noisy which can limit the effectiveness of algorithms. Topological Data Analysis (TDA) is a novel approach that can handle noisy data and may be promising for physiological time series data analysis. However, TDA is currently in the early stages of development, with researchers still grappling with the problem of feature extraction from TDA signatures for machine learning. Current state-of-the-art in TDA handles only small computer vision or univariate time series data analysis due to its computational expense. We present a TDA method for stress detection and validate it on the public Wearable Stress and Affect Detection (WESAD) dataset. We contribute a complete TDA method to classify long multivariate physiological time series data that overcomes some of the computational expensive and demonstrate its effectiveness compared to state of the art methods.
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- 2024
41. Sequence Unlearning for Sequential Recommender Systems
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Liu, T, Yue, L, Webb, G, Wang, D, Ye, S, Lu, J, Liu, T, Yue, L, Webb, G, Wang, D, Ye, S, and Lu, J
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Sequential recommender systems, leveraging clients’ sequential product browsing history, have become an essential tool in delivering personalized product recommendations. As data protection regulations come into focus, certain clients may demand the removal of their data from the training sets used by these systems. In this paper, we focus on the problem of how specific client information can be efficiently removed from a pre-trained sequential recommender system without the need for retraining, particularly when the change to the data set is not substantial. We propose a novel sequence unlearning method for sequential recommender systems by leveraging label noise injection. Intuitively, our method promotes data unlearning by encouraging the system to produce random predictions for the sequences aiming to unlearn. To further prevent the model from overfitting an incorrect label, which could lead to substantial changes in its parameters, our method incorporates a dynamic process wherein the incorrect label is continually altered during the learning phase. This effectively encourages the model to lose confidence in the original label, while also discouraging it from fitting to a specific incorrect label. To the best of our knowledge, this is the first work to tackle the unlearning problem in sequential recommender systems without accessing the remaining data. Our approach is general and can work with any sequential recommender system. Empirically, we demonstrate that our method effectively helps different recommender systems unlearn specific sequential data while maintaining strong generalization performance on the remaining data across different datasets.
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- 2024
42. Improving CCA Algorithms on SSVEP Classification with Reinforcement Learning Based Temporal Filtering
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Liu, T, Yue, L, Webb, G, Wang, D, Ou, L, Do, T, Tran, XT, Leong, D, Chang, Y, Wang, Y, Lin, C, Liu, T, Yue, L, Webb, G, Wang, D, Ou, L, Do, T, Tran, XT, Leong, D, Chang, Y, Wang, Y, and Lin, C
- Abstract
Canonical Correlation Analysis (CCA) has been widely used in Steady-State Visually Evoked Potential (SSVEP) analysis, but there are still challenges in this research area, specifically regarding data quality and insufficiency. In contrast to most previous studies that primarily concentrate on the development of spatial or spectral templates for SSVEP data, this paper proposes a novel temporal filtering method based on a reinforcement learning (RL) algorithm for CCA on SSVEP data. The proposed method leverages RL to automatically and precisely detect and filter low-quality segments in the SSVEP data, thereby improving the accuracy of CCA. Additionally, the proposed RL-based Temporal Filtering is algorithm-independent and compatible with various CCA algorithms. The RL-based Temporal Filtering is evaluated using a wearable dataset consisting of 102 subjects. The experimental results demonstrate significant advancements in CCA accuracy, particularly when combined with the extended CCA (ECCA) algorithm. In addition to performance enhancement, the RL-based Temporal Filtering method provides visualizable filters, which can ensure the transparency of the filtering process and the reliability of the obtained results. By addressing data quality and insufficiency concerns, this novel RL-based Temporal Filtering approach demonstrates promise in advancing SSVEP analysis for various applications.
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- 2024
43. An Augmented Learning Approach for Multiple Data Streams Under Concept Drift
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Liu, T, Yue, L, Webb, G, Wang, D, Wang, K, Lu, J, Liu, A, Zhang, G, Liu, T, Yue, L, Webb, G, Wang, D, Wang, K, Lu, J, Liu, A, and Zhang, G
- Abstract
Multiple data streams learning attracts more and more attention recently. Different from learning a single data stream, the uncertain and complex occurrence of concept drift in multiple data streams, bring challenges in real-time learning task. To address this issue, this paper proposed a method called time-warping-based concept drift learning method (TW-CDM) for dealing with multiple data streams. First, a time-warping-based drift identification process is given to recognize the drift region. Second, an augmented learning process is developed by crossly using the located region data. Finally, a selectively augmented learning process is given to reduce the influence of different drift severity. The proposed method is evaluated on both synthetic and real-world datasets, and compared with benchmark methods. The experiment results show the efficiency of the proposed method.
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- 2024
44. Multiple Teacher Model for Continual Test-Time Domain Adaptation
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Liu, T, Yue, L, Webb, G, Wang, D, Wang, R, Zuo, H, Fang, Z, Lu, J, Liu, T, Yue, L, Webb, G, Wang, D, Wang, R, Zuo, H, Fang, Z, and Lu, J
- Abstract
Test-time adaptation (TTA) without accessing the source data provides a practical means of addressing distribution changes in testing data by adjusting pre-trained models during the testing phase. However, previous TTA methods typically assume a static, independent target domain, which contrasts with the actual scenario of the target domain changing over time. Using previous TTA methods for long-term adaptation often leads to problems of error accumulation or catastrophic forgetting, as it relies on the capability of a single model, leading to performance degradation. To address these challenges, we propose a multiple teacher model approach (MTA) for continual test-time domain adaptation. Firstly, we reduce error accumulation and leverage the robustness of multiple models by implementing a weighted and averaged multiple teacher model that provides pseudo-labels for enhanced prediction accuracy. Then, we mitigate catastrophic forgetting by logging mutation gradients and randomly restoring some parameters to the weights of the pre-trained model. Our comprehensive experiments demonstrate that MTA outperforms other state-of-the-art methods in continual time adaptation.
- Published
- 2024
45. Measurement of the transverse single-spin asymmetry in $p^\uparrow+p \to W^{\pm}/Z^0$ at RHIC
- Author
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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
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- 2015
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46. Rossby Wave Green's Functions in an Azimuthal Wind
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Webb, G. M., Duba, C. T., and Hu, Q.
- Subjects
Physics - Atmospheric and Oceanic Physics - Abstract
Green's functions for Rossby waves in an azimuthal wind are obtained, in which the stream-function $\psi$ depends on $r$, $\phi$ and $t$, where $r$ is cylindrical radius and $\phi$ is the azimuthal angle in the $\beta$-plane relative to the easterly direction, in which the $x$-axis points east and the $y$-axis points north. The Rossby wave Green's function with no wind is obtained using Fourier transform methods, and is related to the previously known Green's function obtained for this case, which has a different but equivalent form to the Green's function obtained in the present paper. We emphasize the role of the wave eikonal solution, which plays an important role in the form of the solution. The corresponding Green's function for a rotating wind with azimuthal wind velocity ${\bf u}=\Omega r{\bf e}_\phi$ ($\Omega=$const.) is also obtained by Fourier methods, in which the advective rotation operator in position space is transformed to a rotation operator in ${\bf k}$ transform space. The finite Rossby deformation radius is included in the analysis. The physical characteristics of the Green's functions are delineated and applications are discussed. In the limit as $\Omega\to 0$, the rotating wind Green's function reduces to the Rossby wave Green function with no wind., Comment: 40 pages, 7 figures
- Published
- 2015
- Full Text
- View/download PDF
47. Centrality dependence of identified particle elliptic flow in relativistic heavy ion collisions at sqrt(s)= 7.7--62.4 GeV
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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
- Full Text
- View/download PDF
48. 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
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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
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- 2015
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49. Multi-Symplectic Magnetohydrodynamics: II, Addendum and Erratum
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Webb, G. M., McKenzie, J. F., and Zank, G. P.
- Subjects
Physics - Plasma Physics - Abstract
A recent paper arXiv:1312.4890 on multi-symplectic magnetohydrodynamics (MHD) using Clebsch variables in an Eulerian action principle with constraints is further extended. We relate a class of symplecticity conservation laws to a vorticity conservation law, and provide a corrected form of the Poincar\'e-Cartan differential form formulation of the system. We also correct some typographical errors (omissions) in arXiv:1312.4890. We show that the vorticity-symplecticity conservation law, that arises as a compatibility condition on the system, expressed in terms of the Clebsch variables is equivalent to taking the curl of the conservation form of the MHD momentum equation. We use the Cartan-Poincar\'e form to obtain a class of differential forms that represent the system using Cartan's geometric theory of partial differential equations., Comment: 12 pages
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- 2015
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50. Probing Parton Dynamics of QCD Matter with $\Omega$ and $\phi$ Production
- Author
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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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