ρ(770)0 and f0(980) production in Au + Au and pp collisions at

Abstract

Preliminary results on ρ(770)0 and f0(980) production at mid-rapidity using the mixed-event technique are presented. The ρ0 and f0 measurements via their hadronic decay channel in minimum bias pp and peripheral Au+Au collisions at were performed using the STAR detector at RHIC. This is the first direct measurement of ρ0(770) → π+π− and f0(980) → π+π− in heavy-ion collisions. The ρ0 mass is transverse momentum dependent and significantly shifted in minimum bias pp and peripheral Au+Au interactions. The modifications of masses, widths and line shapes of short-lived resonances due to phase space and dynamical effects are discussed. The ρ0/π− and the f0/π− ratios are compared to measurements in pp and e+e− interactions at various energies.