High-energy QCD phenomenology with next-to-leading order BFKL eigenfunctions

Abstract

We discuss the phenomenological use of the next-to-leading order (NLO) eigenfunctions of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) kernel. We first recall the BFKL representation of high-energy scattering amplitudes and the role played by the eigenfunctions in the spectral representation of the Green's function. We then compare two equivalent representations of the next-to-leading logarithmic approximation (NLLA) amplitude, respectively based on the leading-order (LO) and NLO eigenfunctions. The two formulations are equivalent within NLLA, while differing by terms beyond this accuracy which could influence the phenomenological stability of high-energy observables. The aim is to test the possible role of NLO eigenfunctions-induced terms in improving this stability, discussing the amplitude dependence on the renormalization and energy scales. As an application, we consider first the forward electroproduction of two light vector mesons and then we comment on preliminary applications to Mueller-Navelet jet production.