Coulomb Effects in Femtoscopy

TL;DR

This paper analyzes Coulomb interactions in femtoscopy, focusing on how they affect correlation functions of identical particles emitted from anisotropic, finite-lifetime sources, including halo effects and relativistic corrections.

Contribution

It provides a detailed analysis of Coulomb effects in femtoscopy, testing the Bowler-Sinyukov procedure for removing Coulomb interactions with considerations of halo and anisotropic sources.

Findings

The Bowler-Sinyukov procedure effectively removes Coulomb effects in ideal conditions.

Halo effects distort correlation functions at small momenta but do not bias source parameter extraction.

Relativistic effects are significant and are thoroughly discussed.

Abstract

The correlation function of two identical particles - pions or kaons - interacting via Coulomb potential is computed. The particles are emitted from an anisotropic particle's source of finite lifetime. In the case of pions, the effect of halo is taken into account as an additional particle's source of large spatial extension. The relativistic effects are discussed in detail. The Bowler-Sinyukov procedure to remove the Coulomb interaction is carefully tested. In the absence of halo the procedure is shown to work very well even for an extremely anisotropic source. When the halo is taken into account the free correlation function, which is extracted by means of the Bowler-Sinyukov procedure, is distorted at small relative momenta but the source parameters are still correctly reproduced.