Interferometry with Resonances and Flow in High-Energy Nuclear Collisions

Abstract

The effects of resonances and flow on the correlation function for two identical particles are described assuming chaotic sources and classical propagation of particles. Expanding to second order in relative momenta, the source sizes can be calculated directly and understood as contributions from various fluctuations in the source. Specific calculations of source size radii are given assuming Bjorken longitudinal flow with additional transverse expansion. Results are compared to recent $ππ$ and $KK$ correlation data from relativistic nuclear collisions with particular attention to the reduction in the $ππ$ correlation function due to resonances and the decreasing source sizes with increasing transverse momenta of the particles.