Quark part of the nonforward BFKL kernel and the “bootstrap” for the gluon Reggeization

Abstract
We calculate the quark part of the kernel of the generalized nonforward BFKL equation at nonzero momentum transfer t in the next-to-leading logarithmic approximation. Along with the quark contribution to the gluon Regge trajectory, this part includes pieces coming from the quark-antiquark production and from the quark contribution to the radiative corrections in one-gluon production in Reggeon-Reggeon collisions. The results obtained can be used for an arbitrary representation of the color group in the t channel. Using the results for the adjoint representation, we demonstrate explicitly the fulfillment of the “bootstrap” condition for the gluon Reggeization in the next-to-leading logarithmic approximation in the part concerning the quark contribution.