  We consider the next-to-leading order (NLO) calculation of single inclusive
particle production at forward rapidities in proton-nucleus collisions and in
the framework of the Color Glass Condensate (CGC). We focus on the quark
channel and the corrections associated with the impact factor. In the first
step of the evolution the kinematics of the emitted gluon is kept exactly (and
not in the eikonal approximation), but such a treatment which includes NLO
corrections is not explicitly separated from the high energy evolution. Thus,
in this newly established "factorization scheme", there is no "rapidity
subtraction". The latter suffers from fine tuning issues and eventually leads
to an unphysical (negative) cross section. On the contrary, our reorganization
of the perturbation theory leads by definition to a well-defined cross section
and the numerical evaluation of the NLO correction is shown to have the correct
size.

High Energy Physics - Phenomenology