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arXiv · 1805.01491

Single-spin asymmetry of $J/ψ$ production in $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions with transversely polarized proton beams at $\sqrt{s_{_{NN}}}=200$ GeV

Abstract

We report the transverse single-spin asymmetries of $J/ψ$ production at forward and backward rapidity, $1.2<|y|<2.2$, as a function of $J/ψ$ transverse momentum ($p_T$) and Feynman-$x$ ($x_F$). The data analyzed were recorded by the PHENIX experiment at the Relativistic Heavy Ion Collider in 2015 from $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions with transversely polarized proton beams at $\sqrt{s_{_{NN}}}=200$ GeV. At this collision energy, single-spin asymmetries for heavy-flavor particle production of $p$$+$$p$ collisions provide access to the spin-dependent gluon distribution and higher-twist correlation functions inside the nucleon, such as the gluon Qiu-Sterman and trigluon correlation functions. Proton+nucleus collisions offer an excellent opportunity to study nuclear effects on the correlation functions. The data indicate negative asymmetries at the two-standard-deviation level in the $p$$+$Au data for $p_T<2$ GeV/$c$ at both forward and backward rapidity, while in $p$$+$$p$ and $p$$+$Al collisions the asymmetries are consistent with zero within the range of experimental uncertainties.

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BibTeXRIS

C. Aidala, Y. Akiba, M. Alfred, V. Andrieux, N. Apadula, H. Asano, B. Azmoun, V. Babintsev, A. Bagoly, N. S. Bandara, K. N. Barish, S. Bathe, A. Bazilevsky, M. Beaumier, R. Belmont, A. Berdnikov, Y. Berdnikov, D. S. Blau, M. Boer, J. S. Bok, M. L. Brooks, J. Bryslawskyj, V. Bumazhnov, S. Campbell, V. Canoa Roman, R. Cervantes, C. Y. Chi, M. Chiu, I. J. Choi, J. B. Choi, Z. Citron, M. Connors, N. Cronin, M. Csanád, T. Csörgő, T. W. Danley, M. S. Daugherity, G. David, K. DeBlasio, K. Dehmelt, A. Denisov, A. Deshpande, E. J. Desmond, A. Dion, D. Dixit, J. H. Do, A. Drees, K. A. Drees, J. M. Durham, A. Durum, A. Enokizono, H. En'yo, S. Esumi, B. Fadem, W. Fan, N. Feege, D. E. Fields, M. Finger, M. Finger, Jr., S. L. Fokin, J. E. Frantz, A. Franz, A. D. Frawley, Y. Fukuda, C. Gal, P. Gallus, P. Garg, H. Ge, F. Giordano, Y. Goto, N. Grau, S. V. Greene, M. Grosse Perdekamp, T. Gunji, H. Guragain, T. Hachiya, J. S. Haggerty, K. I. Hahn, H. Hamagaki, H. F. Hamilton, S. Y. Han, J. Hanks, S. Hasegawa, T. O. S. Haseler, X. He, T. K. Hemmick, J. C. Hill, K. Hill, A. Hodges, R. S. Hollis, K. Homma, B. Hong, T. Hoshino, N. Hotvedt, J. Huang, S. Huang, K. Imai, M. Inaba, A. Iordanova, D. Isenhower. 2018-07-09. Single-spin asymmetry of $J/ψ$ production in $p$$+$$p$, $p$$+$Al, and $p$$+$Au collisions with transversely polarized proton beams at $\sqrt{s_{_{NN}}}=200$ GeV. https://doi.org/10.1103/physrevd.98.012006

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