Special Colloquium, March 10, 2004

High pT Phenomena at RHIC

Saskia Mioduszewski

Brookhaven National Laboratory

The primary goal of colliding heavy ions at ultrarelativistic energies is to achieve a phase transition from ordinary nuclear matter to a deconfined, chirally symmetric phase of quarks and gluons. There are several theoretically proposed signatures of such matter, known as the Quark Gluon Plasma (QGP). One of these is the energy loss of hard-scattered partons traversing the produced (hot and dense) medium.

After three runs of the Relativistic Heavy Ion Collider (RHIC), there is convincing evidence for novel phenomena in the pertinent energy regime (sqrt(s_NN) = 200 GeV). Among the most compelling is the suppression of hadron production at high transverse momenta (pT) in central Au+Au collisions relative to p+p collisions and peripheral Au+Au collisions. In addition, RHIC recently provided d+Au collisions to test the effects of a cold nuclear medium at the same energy.

Results of high pT hadron production in Au+Au, d+Au, and p+p collisions will be shown and compared. The transition between the regimes of soft (low-momentum) and hard (high-momentum) hadron production processes, as well as the virtue of recently extracted photon spectra, will be discussed.

10:30 a.m., Smith Laboratory, Room 1094

Reception in Smith 1094 at 10:00 a.m.