带电粒子前后向多重数关联中pbarp和pp数据明显差异的理论分析
Theoretical analysis for the apparent discrepancy between pbarp and pp data in charged particle forward-backward multiplicity correlations
摘要：
用PYTHIA 6.4程序研究了s^1/2 = 200 GeV的pbar+p和p+p碰撞中带电粒子前向-后向多重关联的强度，并与UA 5和STAR数据进行了比较.结果表明，UA 5和STAR数据之间3-4倍的明显差异可以归因于两个实验中探测器接受度和观测面元间隔的差异。本文介绍了一种混合事件方法，并利用它分别计算了由电荷守恒、四动量守恒和衰变引起的统计关联强度和动力学关联强度。统计关联似乎比动力学关联大得多，而电荷守恒、四动量守恒和衰变可以解释动力学关联的大部分。此外，我们还将PYTHIA的带电粒子多重数分布拟合到负二项分布，计算了关联强度，发现结果与用混合事例计算的关联强度符合得很好。
英文摘要：
The strength of charged particle forward-backward multiplicity correlation in pbar+p and p+p collisions at s^1/2 = 200 GeV is studied by PYTHIA 6.4 and compared to the UA5 and STAR data correspondingly. It is turned out that a factor of 3-4 apparent discrepancy between UA5 and STAR data can be attributed to the differences in detector acceptances and observing bin interval in both experiments. A mixed event method is introduced and used to calculate the statistical correlation strength and the dynamical correlation strengths stemming from the charge conservation, four- momentum conservation, and decay, respectively. It seems that the statistical correlation is much larger than dynamical one and the charge conservation, four-momentum conservation and decay may account for most part of the dynamical correlation. In addition, we have also calculated the correlation strength by fitting the charged particle multiplicity distribution from PYTHIA to the Negative Binomial Distribution and found that the result agrees well with the correlation strength calculated by mixed events.
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。
