Quark TMDs from back-to-back dijet production at forward rapidities in pA collisions beyond eikonal accuracy in the CGC

TL;DR

This paper advances the theoretical understanding of quark transverse momentum dependent distributions (TMDs) in proton-nucleus collisions by including next-to-eikonal corrections from the target's quark background field, providing a more precise description of dijet production at forward rapidities.

Contribution

It introduces a comprehensive calculation of dijet production in pA collisions beyond the eikonal approximation, incorporating next-to-eikonal corrections induced by the target's quark background field.

Findings

Derived a factorized expression for the back-to-back dijet cross section.

Computed scattering amplitudes in general kinematics and the back-to-back limit.

Provided a framework for including next-to-eikonal corrections in TMD studies.

Abstract

We study dijet production in pA collisions at forward rapidities at next-to-eikonal accuracy. We restrict ourselves to the next-to-eikonal corrections that are induced by the quark background field of the target. We consider all possible channels, compute scattering amplitudes both in general kinematics and in the back-to-back limit. By using these results, we compute the back-to-back production cross section and obtain a factorized expression with a quark TMD times associated hard factor for each channel.