Hard to soft pomeron transition in small-x deep inelastic scattering data using optimal renormalization.

ABSTRACT

We show that it is possible to describe the effective Pomeron intercept, determined from the HERA deep inelastic scattering data at small values of Bjorken x, by using next-to-leading order Balitsky-Fadin-Kuraev-Lipatov evolution together with collinear improvements. To obtain a good description over the whole range of Q(2), we use a non-Abelian physical renormalization scheme with the Brodsky-Lepage-Mackenzie optimal scale, combined with a parametrization of the running coupling in the infrared region.