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arXiv · 1906.11763

Asymptotic Charges and Coherent States in QCD

Riccardo Gonzo·Tristan McLoughlin·Diego Medrano·Anne Spiering
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Abstract

We study the connection between asymptotic symmetries in non-Abelian gauge theories and the generalised coherent states following from the application to QCD of the Faddeev-Kulish approach to asymptotic dynamics. We compute the large gauge transformation properties of the soft evolution operators and use this to define the quantum corrected, non-linear contribution to the asymptotic charges. We then compute the one-loop, leading IR-divergent, correction to matrix elements of the charges inserted between dressed scattering states and show that the results depend on a particular order of soft limits. For one choice of ordering we find that the conservation law for the asymptotic charges is not corrected, while for a second we find a correction proportional to the one-loop soft current.

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Riccardo Gonzo, Tristan McLoughlin, Diego Medrano, Anne Spiering. 2019-06-27. Asymptotic Charges and Coherent States in QCD. https://doi.org/10.1103/physrevd.104.025019

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