Femtoscopic correlations of two non-identical particles have a unique
feature, differentiating them from "traditional" identical particle
correlations, of being sensitive to the difference in average emission
position of the two particle types. For pion-kaon pairs the
femtoscopic signal arises from Coulomb interaction between particles.
Its strength is comparable to the magnitude of effects of non-
femtoscopic origin. We identify main sources of these background
correlations as real "physics" correlations coming from elliptic flow.
We propose a robust method to estimate them and account for their
influence in the femtoscopic analysis of experimental data. We
validate the proposed correction method on a data sample generated
with the THERMINATOR 2 model and provide a recipe for experimentalists.
|List of tracks||Femtoscopy at RHIC and LHC: links to QGP physics|