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arXiv · 2407.17557

A QCD R-Axion

James Unwin·Tom Yildirim
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Abstract

R-parity can be extended to a continuous global U(1)${}_R$ symmetry. We investigate whether an anomalous U(1)${}_R$ can be identified as the PQ symmetry suitable for solving the strong CP problem within supersymmetric extensions of the Standard Model. In this case, U(1)${}_R$ is broken at some intermediate scale and the QCD axion is the R-axion. Moreover, the R-symmetry can be naturally gauged via the Green-Schwartz mechanism within completions to supergravity, thus evading the axion quality problem. Obstacles to realizing this scenario are highlighted and phenomenologically viable approaches are identified.

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James Unwin, Tom Yildirim. 2024-07-24. A QCD R-Axion. https://doi.org/10.1103/physrevd.111.015048

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