Jet azimuthal correlations and parton saturation in the color glass condensate

We consider the influence of parton saturation in the color glass condensate on the back-to-back azimuthal correlations of high-P-T hadrons in pA (or dA) collisions. When both near-side and away-side hadrons are detected at mid-rapidity at RHIC energy, the effects of parton saturation are constrained to transverse momenta below the saturation scale P-T less than or equal to Q(s); in this case the back-to-back correlations do not disappear but exhibit broadening. In addition, the uncorrelated background reduces the apparent strength of back-to-back correlations in AA collisions. When near-side and away-side hadrons are separated by several units of rapidity, quantum evolution effects lead to the depletion of back-to-back correlations as a function of rapidity interval between the detected hadrons (at fixed PT). This applies to both pp and pA (or dA) collisions; however, due to the initial conditions provided by the color glass condensate, the depletion of the back-to-back correlations is significantly stronger in the pA case. An experimental study of this effect would thus help to clarify the origin of the high-PT hadron suppression at forward rapidities observed recently at RHIC. (C) 2004 Elsevier B.V. All rights reserved.