Low-p _T spectra of identified charged particles in $\sqrt{s_{NN}}$ = 200 GeV Au+Au collisions from PHOBOS experiment at RHIC

Abstract

The PHOBOS experiment at the Relativistic Heavy Ion Collider (RHIC), comprising the spectrometer with multiple layers of silicon wafers, is an excellent detector for very low transverse momentum (p _T ) particles. Transverse momentum distributions of π^–+π⁺, K^–+K⁺ and $p+\overline{p}$ produced at mid-rapidity are presented for the 15% most central Au-Au collisions at $\sqrt{s_{NN}}$ = 200 GeV. The momentum ranges for measured particles are from 30 to 50 MeV/c for pions, 90 to 130 MeV/c for kaons and 140 to 210 MeV/c for protons and antiprotons. The measurement method is briefly described. A comparison of the p _T spectra to experimental results at higher particle momenta and to model predictions is discussed.

PACS: 25.75.-q