Cold nuclear matter physics at forward rapidities from d+Au collisions in PHENIX
Abstract
We present measurements by the PHENIX experiment at RHIC of di-hadron pair production in collisions where the particles in the pair are varied across a wide range of pseudorapidity, out to η = 3.8. With di-hadrons, varying the pT and rapidity of the particles in the di-hadron pair allows studying any effects as a function of partonic x in the nucleus. These di-hadron measurements might probe down to parton momentum fractions x 10-3 in the gold nucleus, where the interesting possibility of observing gluon saturation effects at RHIC is the greatest. Our measurements show that the correlated yield of back-to-back pairs in collisions is suppressed by up to an order of magnitude relative to collisions, and increases with greater nuclear path thickness and with a selection for lower x in the Au nucleus.