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arXiv · hep-ph/0104038

Parton densities and dipole cross-sections at small x in large nuclei

N. Armesto·M. A. Braun
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Abstract

Unintegrated gluon densities in nuclei, dipole-nucleus cross-sections and quark densities are numerically investigated in the high-colour limit, with the scattering on a heavy nucleus exactly described by the sum of fan diagrams of BFKL pomerons. The initial condition for the evolution in rapidity is quickly forgotten, and the gluon density presents a "supersaturation" pattern, as previous studies indicated. Both dipole-nucleus cross-sections and quark densities present the expected saturation features. Identifying the position in transverse momentum $l$ of the maximum of the gluon distribution with the saturation momentum $Q_s(y,b)$, at large rapidities all distributions depend only on one variable $[l/Q_s(y,b)]$ or $[rQ_s(y,b)]$.

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N. Armesto, M. A. Braun. 2001-04-26. Parton densities and dipole cross-sections at small x in large nuclei. https://doi.org/10.1007/s100520100685

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