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arXiv · 1809.04894

Double longitudinal-spin asymmetries in $J/\psi$ production at RHIC

Yu Feng·Hong-Fei Zhang
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Abstract

The double longitudinal-spin asymmetry, $A_{LL}$, of the $J/\psi$ production in polarized proton-proton collisions is presented in this paper at QCD next-to-leading order. It is found that the obtained values of $A_{LL}$ are in general consistent with the PHENIX measurements. Various sets of the long-distance matrix elements (LDMEs) are employed in our calculation to study the possible theoretical uncertainties. It is found that, for $p_t<5\gev$, all these LDMEs lead to almost the same results, which are within the tolerance of the experimental data uncertainties.

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Yu Feng, Hong-Fei Zhang. 2018-09-13. Double longitudinal-spin asymmetries in $J/\psi$ production at RHIC. https://doi.org/10.1007/jhep11(2018)136

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