The Quark-Antiquark Contribution to the Fully Exclusive BFKL Evolution at NLL Accuracy

Abstract

We calculate the quark-anti-quark contribution to the next-to-leading logarithmic corrections to the BFKL kernel, retaining the dependence on the momenta of the produced particles. This allows us to study the details of the NLL corrections. We demonstrate that the standard calculation of the NLL corrections to the scattering of two off-shell gluons includes contributions from energies far above that which is probed at LL. This explicitly violates energy and momentum conservation in the evolution and could be a source of the reported large NLL corrections. The presented calculation is a step towards combining energy and momentum conservation with full NLL accuracy in the evolution.