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arXiv · 2204.05945

Light vectors coupled to anomalous currents with harmless Wess-Zumino terms

Abstract

We reconsider the case of light vectors coupled to anomalous fermionic currents, focussing on the interplay between UV and IR dynamics. Taking as a general framework the gauging of the Standard Model accidental symmetries, we show that it is possible to devise an anomaly-free UV completion with mostly-chiral heavy fermions such that anomalous Wess-Zumino terms are suppressed in the IR, thus relaxing would-be strong bounds from the longitudinal emission of light vectors coupled to non-conserved currents. We classify such scenarios and show that they will be extensively probed at the high-luminosity phase of the LHC via the measurement of the $h \to Z \gamma$ rate and the direct search for non-decoupling charged leptons.

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Luca Di Luzio, Marco Nardecchia, Claudio Toni. 2022-04-12. Light vectors coupled to anomalous currents with harmless Wess-Zumino terms. https://doi.org/10.1103/physrevd.105.115042

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