Finite size Coulomb correction for interferometry analysis of expanding, partially coherent sources

The problems of the Coulomb correction to the two-boson correlation functions for systems formed in ultra-relativistic heavy ion collisions with large effective volumes are discussed. The modification of the standard zero-distance correction (so-called Gamow or Coulomb factor) has been proposed for such kind of systems. For π+π+ and K+K+ correlation functions the analytical approach for the Coulomb correction is compared with the exact numerical results and good agreement is found at SPS, RHIC and LHC energies. The procedure of an extraction of a possible coherent component in the particle radiation from the particle spectra and two-boson correlation function is proposed. (author)