Effects of source opacity and expansion on two-pion Bose-Einstein correlations

Abstract

We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formalism, where the sources are treated as classical currents with chaotic and coherent components. The two-pion correlation functions of the partially coherent sources contain a phase which is sensitive to the asymmetry of the source emission function. We investigate the influence of source opacity and expansion in high energy heavy ion collisions on the phase by Monte Carlo calculations. We find that these two physical effects shift the phase from zero. The Gaussian-formula fit results to the simulated two-pion correlation functions indicate that the opaque and expansion effects lead to a smaller interferometry radius R out and a larger λ parameter.two-pion correlation, partially coherent sources, asymmetry 25.75.Nq, 25.75.Gz

多重散射效应对部分相干源两粒子关联函数的影响

“…根据源相干部分和混沌部分的物理意义, 可以将源 Wigner 密度函数写成是相干部分和混沌部分之和 [17] : 2 3 4 5 2 2 3 3 2 3 7 5 1 1 2 2 6 12 12 1 1 1 2 4 4…”