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Non-linear evolution in CCFM: the interplay between coherence and saturation

  • Emil Avsar
  • Anna M. Stasto
Open Access
Article

Abstract

We solve the CCFM equation numerically in the presence of a boundary condition which effectively incorporates the non-linear dynamics. We retain the full dependence of the unintegrated gluon distribution on the coherence scale, and extract the saturation momentum. The resulting saturation scale is a function of both rapidity and the coherence momentum. In Deep Inelastic Scattering this will lead to a dependence of the saturation scale on the photon virtuality in addition to the usual x Bj dependence. At asymptotic energies the interplay between the perturbative non-linear physics, and that of the QCD coherence, leads to an interesting and novel dynamics where the saturation momentum itself eventually saturates. We also investigate various implementations of the “non-Sudakov” form factor. It is shown that the non-linear dynamics leads to almost identical results for different form factors. Finally, different choices of the scale of the running coupling are analyzed and implications for the phenomenology are discussed.

Keywords

Deep Inelastic Scattering QCD 

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© The Author(s) 2010

Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

Authors and Affiliations

  1. 1.104 Davey LabPenn State UniversityUniversity ParkU.S.A.
  2. 2.RIKEN CenterBrookhaven National LaboratoryUptonU.S.A.
  3. 3.Institute of Nuclear Physics Polish Academy of SciencesCracowPoland

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