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arXiv · 2002.05948

Probing $e\mu$ flavor-violating ALP at Belle II

Motoi Endo·Syuhei Iguro·Teppei Kitahara
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Abstract

Recently, it was pointed out that the electron and muon g-2 discrepancies can be explained simultaneously by a flavor-violating axion-like particle (ALP). We show that the parameter regions favored by the muon g-2 are already excluded by the muonium-antimuonium oscillation bound. In contrast, those for the electron g-2 can be consistent with this bound when the ALP is heavier than 1.5 GeV. We propose to search for a signature of the same-sign and same-flavor lepton pairs and the forward-backward muon asymmetry to test the model at the Belle II experiment.

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Motoi Endo, Syuhei Iguro, Teppei Kitahara. 2020-02-14. Probing $e\mu$ flavor-violating ALP at Belle II. https://doi.org/10.1007/jhep06(2020)040

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