PHENIX inner detectors

Abstract The timing, location and particle multiplicity of a PHENIX collisionare determined by the Beam–Beam Counters (BBC), the Multiplicity/Vertex Detector ( MVD) and the Zero-Degree Calorimeters (ZDC). The BBCs provide both the time of interaction and position of a collisionfrom the flight time of prompt particles. The MVDprovides a measure of event particle multiplicity, collisionvertex position and fluctuations in charged particle distributions. The ZDCs provide information on the most grazing collisions. A Normalization Trigger Counter (NTC) is used to obtain absolute cross-section measurements for p–p collisions. The BBC, MVDand NTC are described below.