Measurement of Identified Particle Production at RHIC

Identified particle measurements in 200 GeV Au+Au and d+Au collisions in STAR are presented. The importance of using identified particles to probe properties of medium formed at RHIC is emphasized. Magnitude of the nuclear modification factor is observed to depend on particle type (baryon vs meson) instead of particle mass at intermediate transverse momentum. This observation supports recombination/coalescence processes as dominant dynamics for particle production in this transverse momentum region. We argue that φ and heavy quark yields are sensitive to the medium properties at the early stage. The significant suppression of identified particle production observed at high transverse momentum in central Au+Au collisions indicates the formation of strongly‐interacting medium at RHIC.