High-energy factorization via eigenfunctions of the next-to-leading-order BFKL kernel

We present a general formula for the amplitude of forward exclusive hadronic processes in the semihard regime of perturbative Quantum Chromodynamics (QCD), by means of the {\em next-to-leading order} eigenfunctions of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) kernel, as constructed by Chirilli and Kovchegov. We discuss some formal subtleties in the check of compatibility with the similar formula based on the use of the {\em leading-order} BFKL eigenfunctions. Finally, in the specific case of the electroproduction of two light vector mesons, we consider the numerical stability of the amplitude when one or the other set of eigenfunctions is adopted.