Study of the transition from the hard to the soft Pomeron in the small x region using optimal renormalization

We show that it is possible to describe the effective Pomeron intercept using NLO BFKL evolution together with collinear improvements. In order to obtain a good description over the whole range of Q^2 we use a non-Abelian physical renormalization scheme with BLM optimal scale, combined with a parametrization of the running coupling in the infrared region.