New fermions in the light of the $(g-2)_\mu$

J. C. Criado; A. Djouadi; N. Koivunen; K. Müürsepp; M. Raidal; H. Veermäe

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arXiv · 2112.12502

New fermions in the light of the $(g-2)_\mu$

J. C. Criado·A. Djouadi·N. Koivunen·K. Müürsepp·M. Raidal·H. Veermäe

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Abstract

The very precise measurement of the anomalous magnetic moment of the muon, recently released by the Muon g-2 experiment at Fermilab, can serve to set stringent constraints on new particles. If the observed 4$\sigma$ discrepancy from the Standard Model value is indeed real, it will set a tight margin on the scale of the masses and couplings of these particles. Instead, if the discrepancy is simply a result of additional theoretical and experimental uncertainties to be included, strong constraints can be put on their parameters. In this mini-review, we summarize the impact of the latest muon g-2 measurement on new fermions that are predicted by a wide range of new physics models and with exotic quantum numbers and interactions. We will particularly discuss the case of vector-like leptons, excited leptons, and supersymmetric fermions, as well as spin-3/2 isosinglet fermions, which have been advocated recently.

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J. C. Criado, A. Djouadi, N. Koivunen, K. Müürsepp, M. Raidal, H. Veermäe. 2021-12-23. New fermions in the light of the $(g-2)_\mu$. https://arxiv.org/abs/2112.12502

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