Hadrochemical freeze-out parameters and effect of the hadron mass modification in heavy-ion collisions at √S _{N N} = 130 GeV

We apply the chemical freeze-out model to the first available data on hadron yield ratios at the Relativistic Heavy-Ion Collider (RHIC) at √S _{N N} = 130 GeV. The estimated chemical freeze-out temperature at RHIC is similar to that at the Super Proton Synchrotron (SPS), whereas the baryon and the strangeness chemical potentials are much smaller than those at the SPS. The effects of the modification of hadron masses on model parameters are also investigated. The chemical freeze-out temperature and chemical potentials are decreased by including the mass modification of haclrons.