Abstract
We investigate the effects of the saturation boundary on small-x evolution at the next-to-leading order accuracy and beyond. We demonstrate that the instabilities of the next-to-leading order BFKL evolution are not cured by the presence of the saturation boundary. This indicates that a resummation of the higher order corrections is therefore needed also for the nonlinear evolution. The renormalization group improved resummed equation in the presence of the saturation boundary is investigated, and the corresponding saturation scale is extracted. A significant reduction of the saturation scale is found, and we observe that the onset of the saturation corrections is delayed to higher rapidities. This seems to be related to the characteristic feature of the resummed splitting function which at moderately small values of x possesses a minimum.
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Avsar, E., Staśto, A., Triantafyllopoulos, D. et al. Next-to-leading and resummed BFKL evolution with saturation boundary. J. High Energ. Phys. 2011, 138 (2011). https://doi.org/10.1007/JHEP10(2011)138
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DOI: https://doi.org/10.1007/JHEP10(2011)138