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arXiv · hep-ph/9701229

Quantum structure of the non-Abelian Weizsacker-Williams field for a very large nucleus

Yuri V. Kovchegov
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Abstract

We consider the McLerran-Venugopalan model for calculation of the small-$x$ part of the gluon distribution function for a very large ultrarelativistic nucleus at weak coupling. We construct the Feynman diagrams which correspond to the classical Weizsäcker-Williams field found previously [Yu. V. Kovchegov, Phys. Rev. D 54, 5463 (1996)] as a solution of the classical equations of motion for the gluon field in the light-cone gauge. Analyzing these diagrams we obtain a limit for the McLerran-Venugopalan model. We show that as long as this limit is not violated a classical field can be used for calculation of scattering amplitudes.

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Yuri V. Kovchegov. 1997-01-06. Quantum structure of the non-Abelian Weizsacker-Williams field for a very large nucleus. https://doi.org/10.1103/physrevd.55.5445

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