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arXiv 0709.1646nucl-ex
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CERN SPS重离子碰撞多重数涨落的能量、快度和横动量依赖性

Energy, Rapidity and Transverse Momentum Dependence of Multiplicity Fluctuations in Heavy Ion Collisions at CERN SPS

Benjamin Lungwitz

摘要:

本文研究了20A、30A、40A、80A和158AGeV中心Pb+Pb碰撞中产生的正、负和全荷强子在前半球的多重数涨落。多重数分布及其标度方差作为碰撞能量,快度和横向动量的函数。的分布有一个钟形的形状和缩放的方差单调变化的能量范围从0.8到1.2。未观察到临界点的迹象。弦强子模型UrQMD再现的缩放方差的结果。强子共振气体模型的预测内得到的缩放方差的巨正则和正则系综不同意的数据。

英文摘要:

Multiplicity fluctuations in the forward hemisphere were studied for positively, negatively and all charged hadrons produced in central Pb+Pb collisions at 20A, 30A, 40A, 80A and 158A GeV. The multiplicity distributions and their scaled variances are presented as a function of collision energy, rapidity and transverse momentum. The distributions have a bell-like shape and the scaled variance changes monotonously with energy in the range from 0.8 to 1.2. No indication of the critical point is observed. The string-hadronic model UrQMD reproduces results on the scaled variance. The predictions of the hadron-resonance gas model obtained within the grand-canonical and canonical ensembles for the scaled variance disagree with the data.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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