학술논문

Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at $\sqrt{s}=510$ GeV in $\vec{p}+\vec{p}$ Collisions
Document Type
Working Paper
Author
PHENIX CollaborationAbdulameer, N. J.Acharya, U.Adare, A.Aidala, C.Ajitanand, N. N.Akiba, Y.Akimoto, R.Alfred, M.Apadula, N.Aramaki, Y.Asano, H.Atomssa, E. T.Awes, T. C.Azmoun, B.Babintsev, V.Bai, M.Bandara, N. S.Bannier, B.Barish, K. N.Bathe, S.Bazilevsky, A.Beaumier, M.Beckman, S.Belmont, R.Berdnikov, A.Berdnikov, Y.Bichon, L.Black, D.Blankenship, B.Bok, J. S.Borisov, V.Boyle, K.Brooks, M. L.Bryslawskyj, J.Buesching, H.Bumazhnov, V.Campbell, S.Roman, V. CanoaChen, C. -H.Chiu, M.Chi, C. Y.Choi, I. J.Choi, J. B.Chujo, T.Citron, Z.Connors, M.Corliss, R.Morales, Y. CorralesCsanád, M.Csörgő, T.Datta, A.Daugherity, M. S.David, G.Dean, C. T.DeBlasio, K.Dehmelt, K.Denisov, A.Deshpande, A.Desmond, E. J.Ding, L.Dion, A.Doomra, V.Do, J. H.Drees, A.Drees, K. A.Durham, J. M.Durum, A.En'yo, H.Enokizono, A.Esha, R.Fadem, B.Fan, W.Feege, N.Fields, D. E.Finger, Jr., M.Finger, M.Firak, D.Fitzgerald, D.Fokin, S. L.Frantz, J. E.Franz, A.Frawley, A. D.Gallus, P.Gal, C.Garg, P.Ge, H.Giles, M.Giordano, F.Glenn, A.Goto, Y.Grau, N.Greene, S. V.Perdekamp, M. GrosseGunji, T.Guragain, H.Gu, Y.Hachiya, T.Haggerty, J. S.Hahn, K. I.Hamagaki, H.Hanks, J.Han, S. Y.Harvey, M.Hasegawa, S.Hemmick, T. K.He, X.Hill, J. C.Hodges, A.Hollis, R. S.Homma, K.Hong, B.Hoshino, T.Huang, J.Ikeda, Y.Imai, K.Imazu, Y.Inaba, M.Iordanova, A.Isenhower, D.Ivanishchev, D.Jacak, B. V.Jeon, S. J.Jezghani, M.Jiang, X.Ji, Z.Johnson, B. M.Joo, E.Joo, K. S.Jouan, D.Jumper, D. S.Kang, J. H.Kang, J. S.Kawall, D.Kazantsev, A. V.Key, J. A.Khachatryan, V.Khanzadeev, A.Khatiwada, A.Kihara, K.Kim, C.Kim, D. H.Kim, D. J.Kim, E. -J.Kim, H. -J.Kim, M.Kim, T.Kim, Y. K.Kincses, D.Kingan, A.Kistenev, E.Klatsky, J.Kleinjan, D.Kline, P.Koblesky, T.Kofarago, M.Koster, J.Kotov, D.Kovacs, L.Kurgyis, B.Kurita, K.Kurosawa, M.Kwon, Y.Lajoie, J. G.Larionova, D.Lebedev, A.Lee, K. B.Lee, S. H.Leitch, M. J.Leitgab, M.Lewis, N. A.Lim, S. H.Liu, M. X.Li, X.Loomis, D. A.Lynch, D.Lökös, S.Majoros, T.Makdisi, Y. I.Makek, M.Manion, A.Manko, V. I.Mannel, E.McCumber, M.McGaughey, P. L.McGlinchey, D.McKinney, C.Meles, A.Mendoza, M.Meredith, B.Miake, Y.Mignerey, A. C.Miller, A. J.Milov, A.Mishra, D. K.Mitchell, J. T.Mitrankova, M.Mitrankov, Iu.Miyasaka, S.Mizuno, S.Mondal, M. M.Montuenga, P.Moon, T.Morrison, D. P.Moukhanova, T. V.Muhammad, A.Mulilo, B.Murakami, T.Murata, J.Mwai, A.Nagamiya, S.Nagle, J. L.Nagy, M. I.Nakagawa, I.Nakagomi, H.Nakano, K.Nattrass, C.Nelson, S.Netrakanti, P. K.Nihashi, M.Niida, T.Nouicer, R.Novitzky, N.Nukazuka, G.Nyanin, A. S.O'Brien, E.Ogilvie, C. A.Oh, J.Koop, J. D. OrjuelaOrosz, M.Osborn, J. D.Oskarsson, A.Ozawa, K.Pak, R.Pantuev, V.Papavassiliou, V.Park, J. S.Park, S.Patel, L.Patel, M.Pate, S. F.Peng, J. -C.Peng, W.Perepelitsa, D. V.Perera, G. D. N.Peressounko, D. Yu.PerezLara, C. E.Perry, J.Petti, R.Pinkenburg, C.Pinson, R.Pisani, R. P.Potekhin, M.Pun, A.Purschke, M. L.Radzevich, P. V.Rak, J.Ramasubramanian, N.Ravinovich, I.Read, K. F.Reynolds, D.Riabov, V.Riabov, Y.Richford, D.Riveli, N.Roach, D.Rolnick, S. D.Rosati, M.Rowan, Z.Rubin, J. G.Runchey, J.Saito, N.Sakaguchi, T.Sako, H.Samsonov, V.Sarsour, M.Sato, S.Sawada, S.Schaefer, B.Schmoll, B. K.Sedgwick, K.Seele, J.Seidl, R.Sen, A.Seto, R.Sett, P.Sexton, A.Sharma, D.Shein, I.Shibata, M.Shibata, T. -A.Shigaki, K.Shimomura, M.Shi, Z.Shukla, P.Sickles, A.Silva, C. L.Silvermyr, D.Singh, B. K.Singh, C. P.Singh, V.Slunečka, M.Smith, K. L.Soltz, R. A.Sondheim, W. E.Sorensen, S. P.Sourikova, I. V.Stankus, P. W.Stepanov, M.Stoll, S. P.Sugitate, T.Sukhanov, A.Sumita, T.Sun, J.Sun, Z.Sziklai, J.Takahama, R.Takahara, A.Taketani, A.Tanida, K.Tannenbaum, M. J.Tarafdar, S.Taranenko, A.Timilsina, A.Todoroki, T.Tomášek, M.Torii, H.Towell, M.Towell, R.Towell, R. S.Tserruya, I.Ueda, Y.Ujvari, B.van Hecke, H. W.Vargyas, M.Velkovska, J.Virius, M.Vrba, V.Vznuzdaev, E.Wang, X. R.Wang, Z.Watanabe, D.Watanabe, Y.Watanabe, Y. S.Wei, F.Whitaker, S.Wolin, S.Wong, C. P.Woody, C. L.Wysocki, M.Xia, B.Xue, L.Yalcin, S.Yamaguchi, Y. L.Yanovich, A.Yoon, I.Younus, I.Yushmanov, I. E.Zajc, W. A.Zelenski, A.Zou, L.
Source
Subject
High Energy Physics - Experiment
Nuclear Experiment
Language
Abstract
We present measurements of the cross section and double-helicity asymmetry $A_{LL}$ of direct-photon production in $\vec{p}+\vec{p}$ collisions at $\sqrt{s}=510$ GeV. The measurements have been performed at midrapidity ($|\eta|<0.25$) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at $\sqrt{s}=510$ GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range $0.02Comment: 358 authors from 72 institutions, 8 pages, 2 figures, 1 table, 2013 data. v2 is version accepted by Physical Review Letters. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.html