Charged kaon interferometric probes of space-time evolution in Au+Au collisions at sNN=200GeV

Abstract

Bose-Einstein correlations of charged kaons are used to probe Au+Au collisions at sNN=200GeV and are compared to charged pion probes, which have a larger hadronic scattering cross section. Three-dimensional Gaussian source radii are extracted, along with a one-dimensional kaon emission source function. The centrality dependences of the three Gaussian radii are well described by a single linear function of Npart1/3 with a zero intercept. Imaging analysis shows a deviation from a Gaussian tail at r10fm, although the bulk emission at lower radius is well described by a Gaussian. The presence of a non-Gaussian tail in the kaon source reaffirms that the particle emission region in a heavy-ion collision is extended, and that similar measurements with pions are not solely due to the decay of long-lived resonances. © 2009 The American Physical Society.