论文标题
解码A+A碰撞中的QCD关键行为
Decoding the QCD critical behaviour in A+A collisions
论文作者
论文摘要
在核碰撞中的QCD临界点的系统搜索中，在CERN SPS上，发现中央Si+Si碰撞状态的间歇性测量，最大的SPS能量，为我们提供了相当大的关键波动的指示。同样，最近，在（大约）相同能量的10-20％中心碰撞的10-20％的AR+SC反应的初步数据中，效果较弱。但是，分析和实验事件统计的局限性的不确定性使上述测量值（NA49，NA61/Shine）的解释尚无定论，诱使对互补工具和理论思想进行进一步的现象学研究。为此，在目前的工作中，我们在模型独立的分析方案（AMIA）中采用间歇性技术，这是一种来自数据科学的新方法[ARXIV：1205.6505]，以为幂律的参数提供无偏见的结果，尤其是针对关联的Power-Lawsentence（Intermittence Index Index）$ ϕ_2 $。使用不同外围性的数据集，我们还研究了$ ϕ_2 $ - 价值对受伤核子数量的依赖性，以揭示到临界点的方法。借助这些发现以及ISING-QCD分区函数的帮助，讨论了SPS间歇性测量及其与关键区域的联系的解释。
In a systematic search for the QCD critical point in nuclear collisions, at the CERN SPS, it was found that intermittency measurements in the freeze-out state of central Si+Si collisions, at the maximum SPS energy, provide us with an indication of sizeable critical fluctuations. Also, rather recently, a weaker effect was traced in preliminary data of the Ar+Sc reaction for 10-20% most central collisions at (approximately) the same energy. However, the uncertainties in the analysis and the limitations of the experimental event statistics make the interpretation of the above measurements (NA49, NA61/SHINE) rather inconclusive, inviting for a further, phenomenological investigation with complementary tools and theoretical ideas. To this end, in the present work, we employ intermittency techniques within a model-independent analysis scheme (AMIAS), a novel method from Data Science [arXiv:1205.6505], in order to produce unbiased results for the parameters of the power-laws and in particular for the associated power-law exponent (intermittency index) $ϕ_2$. Using data-sets at different peripheralities, we also study the dependence of the $ϕ_2$-value on the number of wounded nucleons, in order to uncover the approach to the critical point. With these findings and the help of Ising-QCD partition function, the interpretation of SPS intermittency measurements and their links to the critical region, are discussed.
