학술논문

Comparison of transverse single-spin asymmetries for forward $\pi^{0}$ production in polarized $pp$, $p\rm{Al}$ and $p\rm{Au}$ collisions at nucleon pair c.m. energy $\sqrt{s_{\mathrm{NN}}}= 200$ GeV
Document Type
Working Paper
Author
STAR CollaborationAdam, J.Adamczyk, L.Adams, J. R.Adkins, J. K.Agakishiev, G.Aggarwal, M. M.Ahammed, Z.Alekseev, I.Anderson, D. M.Aparin, A.Aschenauer, E. C.Ashraf, M. U.Atetalla, F. G.Attri, A.Averichev, G. S.Bairathi, V.Barish, K.Behera, A.Bellwied, R.Bhasin, A.Bielcik, J.Bielcikova, J.Bland, L. C.Bordyuzhin, I. G.Brandenburg, J. D.Brandin, A. V.Butterworth, J.Caines, H.Sánchez, M. Calderón de la BarcaCebra, D.Chakaberia, I.Chaloupka, P.Chan, B. K.Chang, F-H.Chang, Z.Chankova-Bunzarova, N.Chatterjee, A.Chen, D.Chen, J.Chen, J. H.Chen, X.Chen, Z.Cheng, J.Cherney, M.Chevalier, M.Choudhury, S.Christie, W.Chu, X.Crawford, H. J.Csanád, M.Daugherity, M.Dedovich, T. G.Deppner, I. M.Derevschikov, A. A.Didenko, L.Dilks, C.Dong, X.Drachenberg, J. L.Dunlop, J. C.Edmonds, T.Elsey, N.Engelage, J.Eppley, G.Esumi, S.Evdokimov, O.Ewigleben, A.Eyser, O.Fatemi, R.Fazio, S.Federic, P.Fedorisin, J.Feng, C. J.Feng, Y.Filip, P.Finch, E.Fisyak, Y.Francisco, A.Fulek, L.Gagliardi, C. A.Galatyuk, T.Geurts, F.Gibson, A.Gopal, K.Gou, X.Grosnick, D.Guryn, W.Hamad, A. I.Hamed, A.Harabasz, S.Harris, J. W.He, S.He, W.He, X. H.He, Y.Heppelmann, S.Herrmann, N.Hoffman, E.Holub, L.Hong, Y.Horvat, S.Hu, Y.Huang, H. Z.Huang, S. L.Huang, T.Huang, X.Humanic, T. J.Huo, P.Igo, G.Isenhower, D.Jacobs, W. W.Jena, C.Jentsch, A.Ji, Y.Jia, J.Jiang, K.Jowzaee, S.Ju, X.Judd, E. G.Kabana, S.Kabir, M. L.Kagamaster, S.Kalinkin, D.Kang, K.Kapukchyan, D.Kauder, K.Ke, H. W.Keane, D.Kechechyan, A.Kelsey, M.Khyzhniak, Y. V.Kikoła, D. P.Kim, C.Kimelman, B.Kincses, D.Kinghorn, T. A.Kisel, I.Kiselev, A.Kocan, M.Kochenda, L.Koetke, D. D.Kosarzewski, L. K.Kramarik, L.Kravtsov, P.Krueger, K.Mudiyanselage, N. KulathungaKumar, L.Kumar, S.Elayavalli, R. KunnawalkamKwasizur, J. H.Lacey, R.Lan, S.Landgraf, J. M.Lauret, J.Lebedev, A.Lednicky, R.Lee, J. H.Leung, Y. H.Li, C.Li, W.Li, X.Li, Y.Liang, Y.Licenik, R.Lin, T.Lin, Y.Lisa, M. A.Liu, F.Liu, H.Liu, P.Liu, T.Liu, X.Liu, Y.Liu, Z.Ljubicic, T.Llope, W. J.Longacre, R. S.Lukow, N. S.Luo, S.Luo, X.Ma, G. L.Ma, L.Ma, R.Ma, Y. G.Magdy, N.Majka, R.Mallick, D.Margetis, S.Markert, C.Matis, H. S.Mazer, J. A.Minaev, N. G.Mioduszewski, S.Mohanty, B.Mondal, M. M.Mooney, I.Moravcova, Z.Morozov, D. A.Nagy, M.Nam, J. D.Nasim, Md.Nayak, K.Neff, D.Nelson, J. M.Nemes, D. B.Nie, M.Nigmatkulov, G.Niida, T.Nogach, L. V.Nonaka, T.Nunes, A. S.Odyniec, G.Ogawa, A.Oh, S.Okorokov, V. A.Page, B. S.Pak, R.Pandav, A.Panebratsev, Y.Pawlik, B.Pawlowska, D.Pei, H.Perkins, C.Pinsky, L.Pintér, R. L.Pluta, J.Porter, J.Posik, M.Pruthi, N. K.Przybycien, M.Putschke, J.Qiu, H.Quintero, A.Radhakrishnan, S. K.Ramachandran, S.Ray, R. L.Reed, R.Ritter, H. G.Rogachevskiy, O. V.Romero, J. L.Ruan, L.Rusnak, J.Sahoo, N. R.Sako, H.Salur, S.Sandweiss, J.Sato, S.Schmidke, W. B.Schmitz, N.Schweid, B. R.Seck, F.Seger, J.Sergeeva, M.Seto, R.Seyboth, P.Shah, N.Shahaliev, E.Shanmuganathan, P. V.Shao, M.Sheikh, A. I.Shen, W. Q.Shi, S. S.Shi, Y.Shou, Q. Y.Sichtermann, E. P.Sikora, R.Simko, M.Singh, J.Singha, S.Smirnov, N.Solyst, W.Sorensen, P.Spinka, H. M.Srivastava, B.Stanislaus, T. D. S.Stefaniak, M.Stewart, D. J.Strikhanov, M.Stringfellow, B.Suaide, A. A. P.Sumbera, M.Summa, B.Sun, X. M.Sun, X.Sun, Y.Surrow, B.Svirida, D. N.Szymanski, P.Tang, A. H.Tang, Z.Taranenko, A.Tarnowsky, T.Thomas, J. H.Timmins, A. R.Tlusty, D.Tokarev, M.Tomkiel, C. A.Trentalange, S.Tribble, R. E.Tribedy, P.Tripathy, S. K.Tsai, O. D.Tu, Z.Ullrich, T.Underwood, D. G.Upsal, I.Van Buren, G.Vanek, J.Vasiliev, A. N.Vassiliev, I.Videbæk, F.Vokal, S.Voloshin, S. A.Wang, F.Wang, G.Wang, J. S.Wang, P.Wang, Y.Wang, Z.Webb, J. C.Weidenkaff, P. C.Wen, L.Westfall, G. D.Wieman, H.Wissink, S. W.Witt, R.Wu, Y.Xiao, Z. G.Xie, G.Xie, W.Xu, H.Xu, N.Xu, Q. H.Xu, Y. F.Xu, Y.Xu, Z.Yang, C.Yang, Q.Yang, S.Yang, Y.Yang, Z.Ye, Z.Yi, L.Yip, K.Yu, Y.Zbroszczyk, H.Zha, W.Zhang, C.Zhang, D.Zhang, S.Zhang, X. P.Zhang, Y.Zhang, Z. J.Zhang, Z.Zhao, J.Zhong, C.Zhou, C.Zhu, X.Zhu, Z.Zurek, M.Zyzak, M.
Source
Phys. Rev. D 103, 072005 (2021)
Subject
Nuclear Experiment
High Energy Physics - Experiment
Language
Abstract
The STAR Collaboration reports a measurement of the transverse single-spin asymmetries, $A_{N}$, for neutral pions produced in polarized proton collisions with protons ($pp$), with aluminum nuclei ($p\rm{Al}$) and with gold nuclei ($p\rm{Au}$) at a nucleon-nucleon center-of-mass energy of 200 GeV. Neutral pions are observed in the forward direction relative to the transversely polarized proton beam, in the pseudo-rapidity region $2.7<\eta<3.8$. Results are presented for $\pi^0$s observed in the STAR FMS electromagnetic calorimeter in narrow Feynman x ($x_F$) and transverse momentum ($p_T$) bins, spanning the range $0.172.5$ GeV/$c$. It is further observed that the value of $A_N$ is significantly larger for events with a large-$p_T$ isolated $\pi^0$ than for events with a non-isolated $\pi^0$ accompanied by additional jet-like fragments. The nuclear dependence $r(A)$ is similar for isolated and non-isolated $\pi^0$ events.