Reggeization of the quark-quark scattering amplitude in QCD

Abstract

$s$-channel discontinuity of the quark-quark scattering amplitude with gluon quantum numbers in the $t$ channel and a negative signature is calculated in the Regge kinematical region in the two-loop approximation. Using this discontinuity and assuming that the Regge asymptotic behavior is given by the Reggeized gluon contribution, we calculate the gluon trajectory in the two-loop approximation. Remarkable cancellations lead to the independence of the trajectory on properties of the scattered quarks, confirming the gluon Reggeization.