论文标题
RHIC和LHC能量中化学冷冻参数和陌生平衡的中心性依赖性
Centrality dependence of chemical freeze-out parameters and strangeness equilibration in RHIC and LHC energies
论文作者
论文摘要
我们估计了从$π^\ pm $，$ k^\ pm $和$ p $，$ \ bar {p} $ collision collision Energies（相对性重新离子collider），Beam Energy Collider（Rhic-Bes）计划（Rhic-BES）和LHC（大型HADRON COLLIRER）（大型HADRON Collider）的碰撞能量的化学冷冻参数的中心性变化。我们考虑了一个简单的强子共振气体模型，并采用了涉及QCD的保守费用（$ b，q，s $）的形式主义进行参数化。除了温度和三个化学势（$ t，μ_b，μ_q，μ_s$）外，陌生性不饱和因子（$γ_s$）已被用来在奇怪的扇区中纳入部分平衡。我们获得的冷冻温度随中心性的变化不大，而化学电位和$γ_S$似乎具有显着依赖性。发现奇怪的哈德子在外围碰撞时冻结时偏离完全的化学平衡。随着在较低的Rhic-BES能量下碰撞能量降低，这种偏差似乎更为突出。我们还表明，从平衡降低到中央碰撞的情况下，奇怪的粒子平衡可能会在$ a $ a-$ a $碰撞的阈值参与者数量之后发生。
We have estimated centrality variation of chemical freeze-out parameters from yield data at mid-rapidity of $π^\pm$, $K^\pm$ and $p$, $\bar{p}$ for collision energies of RHIC (Relativistic Heavy Ion Collider), Beam Energy Scan (RHIC-BES) program, and LHC (Large Hadron Collider). We have considered a simple hadron resonance gas model and employed a formalism involving conserved charges ($B, Q, S$) of QCD for parameterization. Along with temperature and three chemical potentials ($T,μ_B,μ_Q,μ_S$), a strangeness under-saturation factor ($γ_S$) has been used to incorporate the partial equilibration in the strange sector. Our obtained freeze-out temperature does not vary much with centrality, whereas chemical potentials and $γ_S$ seem to have a significant dependence. The strange hadrons are found to deviate from a complete chemical equilibrium at freeze-out at the peripheral collisions. This deviation appears to be more prominent as the collision energy decreases at lower RHIC-BES energies. We have also shown that this departure from equilibrium reduces towards central collisions, and strange particle equilibration may happen after a threshold number of participants in $A$-$A$ collision.
