标题： LHC能区重离子碰撞中$B_c$介子的统计产生机制 显示英文标题

标题： Statistical Production of $B_c$ Mesons in Heavy-Ion Collisions at the LHC Energy

摘要： 在LHC能区重离子碰撞中，通过传输到去禁闭介质中的大量且高度热化的粲夸克（$c$），促进了$B_c$介子的重组产生。 We study the production of $B_c$ mesons via $c$ and bottom ($b$) quark recombination in a statistical fashion by placing $B_c$ in the position of a member of the family of open $b$ hadrons, which allows us to make quantitative predictions for the modifications of the production fraction ($f_c$) of $B_c$ mesons and its relative production to $B$ mesons in $\sqrt{s_{\rm NN}}=5.02$ TeV Pb-Pb collisions with respect to proton-proton ($pp$) collisions at the same energy. $B_c$ 介子的统计产量被转化为横动量 ($p_T$) 分布，其形状通过共振重组计算得出，使用的 $c$- 和 $b$-夸克相空间分布是通过 Langevin 扩散模拟并由开放的 $c$- 和 $b$- 强子可观测量约束得到的。 补充了来自$b$夸克谱的碎片成分（在高$p_T$区域占主导），得到了$B_c$介子的总$p_T$谱，并将其转化为与$p_T$相关的核修正因子（$R_{\rm AA}$）。 Both $f_c$ and the integrated $R_{\rm AA}$ exhibit a $\sim5$-fold enhancement in central Pb-Pb collisions relative to the $pp$ reference. Comparison with data measured by the CMS experiment shows decent agreement within theoretical and experimental uncertainties. 显示英文摘要

摘要： The recombination production of $B_c$ mesons in heavy-ion collisions at the LHC energy is facilitated by the abundant and highly thermalized charm ($c$) quarks transported in the deconfined medium created. We study the production of $B_c$ mesons via $c$ and bottom ($b$) quark recombination in a statistical fashion by placing $B_c$ in the position of a member of the family of open $b$ hadrons, which allows us to make quantitative predictions for the modifications of the production fraction ($f_c$) of $B_c$ mesons and its relative production to $B$ mesons in $\sqrt{s_{\rm NN}}=5.02$ TeV Pb-Pb collisions with respect to proton-proton ($pp$) collisions at the same energy. The statistical production yield of $B_c$ mesons is converted into the transverse momentum ($p_T$) distribution with the shape computed from resonance recombination using the $c$- and $b$-quark phase space distributions that have been simulated via Langevin diffusion and constrained by open $c$- and $b$-hadron observables. Supplemented with the component fragmented from $b$-quark spectrum that dominates at high $p_T$, the total $p_T$ spectrum of $B_c$ mesons is obtained and converted into the $p_T$ dependent nuclear modification factor ($R_{\rm AA}$). Both $f_c$ and the integrated $R_{\rm AA}$ exhibit a $\sim5$-fold enhancement in central Pb-Pb collisions relative to the $pp$ reference. Comparison with data measured by the CMS experiment shows decent agreement within theoretical and experimental uncertainties.