Improvement for Color Glass Condensate factorization: single hadron production in pA collisions at next-to-leading order

Abstract

High order calculation at semi-hard scale is very important, but a satisfactory calculation framework is still missing. We propose a systematic method to regularize rapidity divergences in the CGC factorization, which makes higher order calculation rigorous and straight forward. By applying this method to single hadron production in pA collision, we find the kinematic constraint effect introduced by hand in previous works comes out automatically, but with different values. The difference is crucial for our next-to-leading order (NLO) result to have a smaller theoretical uncertainty comparing with LO result, which makes high order calculation in CGC factorization to be useful. As a byproduct, the negativity problem found in literature can also be overcome in our framework by a proper choosing of factorization scale.

10 pages, 3 figures, published version

References in corpus (13)

• Parton distributions for the LHC
• The Color Glass Condensate
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Cited by in corpus (4)

• NLO impact factor for inclusive photon$+$dijet production in $e+A$ DIS at small $x$
• Transverse Parton Distribution and Fragmentation Functions at NNLO: the Gluon Case
• Pursuing the Precision Study for Color Glass Condensate in Forward Hadron Productions
• Saturation and forward jets in proton-lead collisions at the LHC