High energy Pb+Pb collisions viewed by pion interferometry

Abstract

Two-pion correlations from Pb+Pb collisions at 158 $\mathrm{GeV}/c$ per nucleon are measured by the NA44 experiment at CERN. Multidimensional fits characterize the emission volume, which is found to be larger than in S-induced collisions. Comparison to the RQMD model is used to relate the fit parameters to the actual emission volume.