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arXiv · 2104.03489

Muon anomalous magnetic dipole moment in the $\mu\nu$SSM

Abstract

Recently, the Muon g-2 experiment at Fermilab has measured the muon anomalous magnetic dipole moment (MDM), $a_\mu=(g_\mu-2)/2$, which reported that the new experimental average increases the tension between experiment and the standard model (SM) prediction to 4.2$\sigma$. In this work, we reanalyse the muon anomalous MDM at two-loop level in the $\mu$ from $\nu$ Supersymmetric Standard Model ($\mu\nu$SSM) combined with the updated experimental average. The $\mu\nu$SSM can explain the current tension between the experimental measurement and the SM theoretical prediction for the muon anomalous MDM, constrained by the 125 GeV Higgs boson mass and decays, the rare decay $\bar{B}\rightarrow X_s\gamma$ and so on. We also investigate the anomalous MDM of the electron and tau lepton, $a_e=(g_e-2)/2$ and $a_\tau=(g_\tau-2)/2$, at two-loop level in the $\mu\nu$SSM. In addition, the 125 GeV Higgs boson decays to a pair of charged leptons in the $\mu\nu$SSM are also analysed.

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Hai-Bin Zhang, Chang-Xin Liu, Jin-Lei Yang, Tai-Fu Feng. 2021-04-08. Muon anomalous magnetic dipole moment in the $\mu\nu$SSM. https://doi.org/10.1088/1674-1137/ac71a6

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