标题： $J/ψ$与直接光子在非相对论QCD和ICEM中的关联产生以及高能因子化方法的应用 显示英文标题

标题： Associated production of $J/ψ$ and direct photon in the NRQCD and the ICEM using the high-energy factorization

摘要： 我们研究在高能因子化框架下，通过部分子瑞奇化方法表述的关联$J/{\psi}$和直接光子产生，使用两种不同的模型将重夸克-反夸克对强子化为重夸克介子，即非相对论量子色动力学（NRQCD）和改进的颜色蒸发模型（ICEM）。 我们发现使用 NRQCD 和 ICEM 得到的截面和横向动量谱的预测存在显著差异，这些差异可用于区分这两种模型。 我们在 LHC 能量下对关联$J/{\psi}$和直接光子产生的截面预测略微高估了在共线部分子模型（CPM）中早期进行的下一阶（NLO）计算结果。 我们预测了关联$J/{\psi}$和直接光子产生中的不同粒子相关谱，这可能对实验研究有重要意义。 显示英文摘要

摘要： We study the associated $J/{\psi}$ and direct photon production in the high-energy factorization, as it is formulated in the parton Reggeization approach, using two different models for the hadronization of a heavy quark-antiquark pair into a heavy quarkonium, namely the non-relativistic quantum chromodynamics (NRQCD) and the improved color evaporation model (ICEM). We find essential differences in the predictions for cross-section and transverse momenta spectra obtained using the NRQCD and the ICEM, which can be used to discriminate between these models. Our prediction for cross-sections of the associated $J/{\psi}$ and direct photon production at the LHC energies slightly overestimates the results obtained early in the next-to-leading order (NLO) calculation in the collinear parton model (CPM). We predict different two-particle correlation spectra in the associated $J/{\psi}$ and direct photon production which may be of interest for experimental study.