标题： charm介子在$pp$和AA碰撞中的产生 显示英文标题

标题： Charm-hadron production in $pp$ and AA collisions

摘要： 最近在LHC中对$pp$、$p$-铅和铅-铅碰撞中各种奇夸克介子比值的测量，对重夸克强子化理论理解提出了挑战。 $\Lambda_c/D^0$比例在$pp$和$p$-Pb 碰撞中表现出比在$e^+e^-$和$ep$碰撞中发现的值以及基于字符串碎片化的蒙特卡罗事件生成器的预测值更大的数值，在低和中间横向动量（$p_T$）下均如此。 在AA碰撞中，$D_s/D$比值显著高于在$pp$中的值，而$\Lambda_c/D^0$数据表明在中间$p_T$处有进一步的增强。这里，我们报告了我们在全面描述魅强子化学和在$pp$和$AA$碰撞中的输运方面的最新进展。 对于$pp$碰撞，我们发现通过使用一个统计强子化模型，并引入一组大量的“缺失”态在重子谱中，从而通过衰变下流对$\Lambda_c$作出贡献，使得$\Lambda_c/D^0$数据与模型预测之间的差异大大减少。 对于$AA$碰撞，我们开发了一个动量守恒的共振重组模型，用于描述重子形成，该模型通过逐事件模拟实现，考虑了传输的重夸克和热轻夸克分布中的空间-动量相关性（SMCs）。 SMCs 以及增强的重子态被发现对于描述中间动量区域的重子-介子增强起着重要作用。 我们强调在使用凝聚模型计算重子化学及其动量依赖性时，满足正确的（相对）化学平衡极限的重要性。 显示英文摘要

摘要： Recent measurements of various charm-hadron ratios in $pp$, $p$-Pb and Pb-Pb collisions at the LHC have posed challenges to the theoretical understanding of heavy-quark hadronization. The $\Lambda_c/D^0$ ratio in $pp$ and $p$-Pb collisions shows larger values than those found in $e^+e^-$ and $ep$ collisions and predicted by Monte-Carlo event generators based on string fragmentation, at both low and intermediate transverse momenta ($p_T$). In AA collisions, the $D_s/D$ ratio is significantly enhanced over its values in $pp$, while the $\Lambda_c/D^0$ data indicates a further enhancement at intermediate $p_T$. Here, we report on our recent developments for a comprehensive description of the charm hadrochemistry and transport in $pp$ and $AA$ collisions. For $pp$ collisions we find that the discrepancy between the $\Lambda_c/D^0$ data and model predictions is much reduced by using a statistical hadronization model augmented by a large set of "missing" states in the charm-baryon spectrum, contributing to the $\Lambda_c$ via decay feeddown. For $AA$ collisions, we develop a 4-momentum conserving resonance recombination model for charm-baryon formation implemented via event-by-event simulations that account for space-momentum correlations (SMCs) in transported charm- and thermal light-quark distributions. The SMCs, together with the augmented charm-baryon states, are found to play an important role in describing the baryon-to-meson enhancement at intermediate momenta. We emphasize the importance of satisfying the correct (relative) chemical equilibrium limit when computing the charm hadrochemistry and its momentum dependence with coalescence models.