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arXiv · 2603.17791

On the size of gluon occupancies in saturation

Abstract

The size of gluon occupancies, or equivalently the nuclear gluon TMD, at gluon transverse momentum $k_\perp \le Q_s(Y)$ is evaluated. Without Sudakov corrections the occupations can become arbitrarily large while Sudakov effects lead to maximum occupancies of size $(1/\alpha)^{3/2}$. Results are the same for running coupling and fixed coupling dynamics. The coherent (elastic) TMD and inelastic gluon TMD are the same in the gluon saturation region. The saturated gluons in the light cone wavefunction seem to have little or no interaction among themselves.

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A. H. Mueller. 2026-03-18. On the size of gluon occupancies in saturation. https://arxiv.org/abs/2603.17791

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