The Search for Gluon Saturation in pA Collisions

In this talk, I reviewed the recent theoretical progress towards the exploration of the gluon saturation phenomenon in $pA$ collisions at both RHIC and the LHC. Two important pillars of this exploration are the single inclusive forward hadron productions and forward dihadron correlations, which have both been computed up to one-loop order within the small-$x$ factorization formalism. Furthermore, detailed numerical study for the single inclusive hadron production at next-to-leading order provides us good description of the low transverse momentum data measured in $dAu$ collisions at RHIC with significantly reduced uncertainty. In addition, the one-loop calculation for dihadron productions in $pA$ collisions shows that there is a new type of large logarithm, which is known as the Sudakov factor, arising in the back-to-back correlation limit.