The double longitudinal-spin asymmetry, ALL, of the J/ψ 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 ALL 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 pt<5\gev, all these LDMEs lead to almost the same results, which are within the tolerance of the experimental data uncertainties.
@article{arxiv.1809.04894,
title = {Double longitudinal-spin asymmetries in $J/\psi$ production at RHIC},
author = {Yu Feng and Hong-Fei Zhang},
journal= {arXiv preprint arXiv:1809.04894},
year = {2018}
}