Abstract: | Correlations between non-identical particles at small relative velocity probe asymmetries in the average space-time emission
points at freezeout 1]. Such asymmetries may arise from long-lived resonances, bulk collective effects, or differences in
the freezeout scenario for the different particle species. STAR has extracted pion-proton correlation functions from a high-statistics
dataset of Au+Au collisions at ?{sNN }\sqrt {s_{NN} } = 200 GeV. We present a femtoscopic analysis of this data for all combinations of charged pions and (anti-) protons, for
collisions of different centrality. The measurements are compared with calculations of a simple Blast-wave model, in which
asymmetries are driven only by collective flow, as well as with Therminator 2], which also accounts fully for resonance effects. |