Multiple scattering effects on boson interferometry in high energy heavy-ion collisions

The goal of the present study is to see to what extent a ‘‘pure’’ multiple scattering model can describe recent boson interferometry measurements which have been carried out at the CERN SPS. Assuming an initially spherical spacial distribution of the produced particles and with multiplicities, ${\mathit{p}}_{\mathit{T}}$ distributions, and rapidity-distributions taken from experiment, the position and momentum of each particle are allowed to evolve in time while undergoing multiple scatterings with the other particles in the system until freezeout for that particle occurs. Pions, kaons, and nucleons are included in the calculations but no resonance production of hadrons is included. From the resulting space-time and momentum information for each boson, bosons are symmetrized in pairs, a two-boson correlation function is formed, and a Gaussian source parametrization is fitted to extract the radius parameter for the source. It is found that although the present model radius parameters tend to be systematically slightly smaller than the experimental ones in some cases, the ‘‘pure’’ multiple scattering calculation describes well the experimental rapidity, ${\mathit{p}}_{\mathit{T}}$, and boson-type dependences observed at CERN energies.