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arXiv 0709.2477nucl-ex
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由中心Pb+Pb碰撞中两质子和两氘核关联计算靶快度时的源半径GeV

Source radii at target rapidity from two-proton and two-deuteron correlations in central Pb+Pb collisions at 158 A GeV

WA98 Collaboration, M. M. Aggarwal

摘要:

本文研究了158 AGeV中心Pb+Pb碰撞靶碎裂区的双质子和双氘核关联。质子和氘核是用CERN SPS的WA 98实验的塑料球光谱仪测量的。利用Bertsch-Pratt和Yano-Koonin-Podgoretsky参数化的两粒子关联函数的一维和多维分析结果。质子源表现出体积发射,而氘核源,具有小的向外半径,出现不透明。质子源和氘核源的交叉项R_{ol} ^2和纵向速度β均为零,表明它们是一种助推不变膨胀。不变半径参数R遵循近似A/sqrt{m}标度,而纵向和横向半径R_{L}和R_{T}在两种情况下都近似为A/sqrt{ m_{T} },其中A ~ 3 fm GeV^{1/2}。

英文摘要:

Two-proton and two-deuteron correlations have been studied in the target fragmentation region of central Pb+Pb collisions at 158 A GeV. Protons and deuterons were measured with the Plastic Ball spectrometer of the WA98 experiment at the CERN SPS. The results of one-dimensional and multi-dimensional analyses using both the Bertsch-Pratt and Yano-Koonin-Podgoretsky parameterizations of the two-particle correlation functions are presented. The proton source exhibits a volume emission, while the deuteron source, with small outward radius, appears opaque. Both proton and deuteron sources have cross-terms R_{ol}^2 and longitudinal velocities beta consistent with zero, indicating a boost-invariant expansion. The invariant radius parameter R follows an approximate A/sqrt{m} scaling while the longitudinal and transverse radii, R_{L} and R_{T}, scale approximately as A/sqrt{m_{T}} with A ~ 3 fm GeV^{1/2} in both cases.

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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