Heavy ion experiments at the relativistic heavy ion collider

Heavy Ion experiments at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory are designed to search for signatures of quark-gluon plasma and enhance our understanding of the behaviour of strongly interacting matter under extreme conditions. RHIC, as the first dedicated heavy ion collider facility, can collide Au–Au beams at a center-of-mass energy of up to sNN=200 GeV per nucleon pair, thus achieving energy densities higher than any previous heavy ion physics program. Four experiments have been constructed and have just concluded their first physics run to investigate these collisions: BRAHMS, PHENIX, PHOBOS, STAR. After a brief introduction to the general features of heavy ion experiments at RHIC, this paper will describe which technologies are used for various detector sub-systems and what their particular strength in the physics program is. Special emphasis will be given to detector systems which were already commissioned during the first physics run in summer 2000 and, where possible, first experiences with their performance shall be reported.