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.
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Avsar, E., Stasto, A.M. Non-linear evolution in CCFM: the interplay between coherence and saturation. J. High Energ. Phys. 2010, 112 (2010). https://doi.org/10.1007/JHEP06(2010)112
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DOI: https://doi.org/10.1007/JHEP06(2010)112