Multiboson Effects in Bose–Einstein Interferometry and the Multiplicity Distribution

Abstract

Multiboson symmetrization effects on two-particle Bose-Einstein interferometry are studied for ensembles with arbitrary multiplicity distributions. This generalizes the previously studied case of a Poissonian input multiplicity distribution. In the general case we find interesting residual correlations which require a modified framework for extracting information on the source geometry from two-particle correlation measurements. In sources with high phase-space densities, multiboson effects modify the Hanbury Brown-Twiss (HBT) radius parameters and simultaneously generate strong residual correlations. We clarify their effect on the correlation strength (intercept parameter) and thus explain a variety of previously reported puzzling multiboson symmetrization phenomena. Using a class of analytically solvable Gaussian source models, with and without space-momentum correlations, we present a comprehensive overview of multiboson symmetrization effects on particle interferometry. For event ensembles of (approximately) fixed multiplicity, the residual correlations lead to a minimum in the correlation function at nonzero relative momentum, which can be practically exploited to search, in a model-independent way, for multiboson symmetrization effects in high-energy heavy-ion experiments. C

Correlation femtoscopy

“…As for f , it increases with energy and for central lead-lead or gold-gold collisions seems to saturate at the highest SPS energy [33,45] (see, however, [46]). The saturated f is substantially smaller than unity for pions with p t > 0.2 Gev/c so pointing to negligible multiboson effects (see, e.g., [47,48]) in this p t -region.…”

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