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arXiv · 2006.11171

Revisiting the proton mass decomposition

Andreas Metz·Barbara Pasquini·Simone Rodini
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Abstract

Different decompositions (sum rules) for the proton mass have been proposed in the literature. All of them are related to the energy-momentum tensor in quantum chromodynamics. We review and revisit these decompositions by paying special attention to recent developments with regard to the renormalization of the energy-momentum tensor. The connection between the sum rules is discussed as well. We present numerical results for the various terms of the mass decompositions up to 3 loops in the strong coupling, and consider their scheme dependence. We also elaborate on the role played by the trace anomaly and the sigma terms.

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Andreas Metz, Barbara Pasquini, Simone Rodini. 2020-06-19. Revisiting the proton mass decomposition. https://doi.org/10.1103/physrevd.102.114042

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