The BFKL-Regge expansion for the proton structure function at small $x$

Abstract

We report an evaluation of subleading eigenvalues and eigenfunctions of the BFKL equation in the color dipole representation with a running gauge coupling. We present an expansion of the small-$x$ proton structure function $F_{2p}(x,Q^2)$ in terms of the rightmost BFKL-singularities. The BFKL-Regge phenomenology of DIS structure functions is developed which is shown to provide remarkably good description of the data on $F_{2p}(x,Q^2)$ from E665 to HERA.