Large angle hadron correlations from medium-induced gluon radiation

Final state medium-induced gluon radiation in ultradense nuclear matter is examined and shown to favor large angle emission when compared to vacuum bremsstrahlung due to the suppression of collinear gluons. Perturbative expression for the contribution of its hadronic fragments to the back-to-back particle correlations is derived. It is found that in the limit of large jet energy loss gluon radiation determines the yield and angular distribution of vertical bar Delta phi vertical bar >= (pi)/(2) dihadrons to high transverse momenta p(T2) of the associated particles. Clear transition from enhancement to suppression of the away-side hadron correlations is established at moderate p(T2) and its experimentally accessible features are predicted versus the trigger particle momentum p(T1). (c) 2005 Elsevier B.V. All rights reserved.