English

Small x resummations confronted with F_2(x,Q^2) data

High Energy Physics - Phenomenology 2014-11-17 v3

Abstract

It has been observed recently that a consistent LO BFKL gluon evolution leads to a steep growth of F_2(x,Q^2) for x -> 0 almost independently of Q^2. We show that current data from the DESY HERA collider are precise enough to finally rule out a pure BFKL behaviour in the accessible small x region. Several attempts have been made by other groups to treat the BFKL type small x resummations instead as additions to the conventional anomalous dimensions of the successful renormalization group ``Altarelli-Parisi'' equations. We demonstrate that all presently available F_2 data, in particular at lower values of Q^2, can not be described using the presently known NLO (two-loop consistent) small x resummations. Finally we comment on the common reason for the failure of these BFKL inspired methods which result, in general, in too steep x-dependencies as x -> 0.

Keywords

Cite

@article{arxiv.hep-ph/9609378,
  title  = {Small x resummations confronted with F_2(x,Q^2) data},
  author = {I. Bojak and M. Ernst},
  journal= {arXiv preprint arXiv:hep-ph/9609378},
  year   = {2014}
}

Comments

Revised, to be published in Phys. Lett. B., 18 pages, LaTeX2e, 3 figures, uses amssymb and epsfig styles

R2 v1 2026-07-22T14:33:25.750Z