The Quark Impact Factors

TL;DR

This paper computes next-to-leading order non-forward quark impact factors for singlet and octet color states in QCD, verifying the bootstrap condition for gluon Reggeization and providing explicit massless quark results.

Contribution

It introduces a comprehensive calculation of impact factors in arbitrary dimensions, confirming the bootstrap condition at NLO, and explicitly evaluates massless quark impact factors.

Findings

Bootstrap condition is satisfied for both helicity parts.

Impact factors are explicitly calculated for massless quarks.

Verification of gluon Reggeization at NLO.

Abstract

We calculate in the next-to-leading approximation the non-forward quark impact factors for both singlet and octet color representation in the $t$-channel. The integral representation of the octet impact factor in the general case of arbitrary space-time dimension and massive quark flavors is used to check the so-called "second bootstrap condition" for the gluon Reggeization at the next-to-leading logarithmic approximation in perturbative QCD. We find that it is satisfied for both helicity conserving and non-conserving parts. The integrations are then performed for the explicit calculation of the impact factors in the massless quark case.