Very recently, the Fermi-Lab reported the new experimental combined results on the magnetic momentum of muon with a 4.2 discrepancy compared with the expectation of the Standard Model \cite{Fermi_Lab}. A new light gauge boson in the model provides a good explanation for the anomaly. A Dirac fermion dark matter with a large charge can explain both the anomaly and the dark matter relic density \cite{Asai_2021}. In this work, we focus on the case that the mass of the dark matter is larger than the mass of muon (i.e. ) for which the channel opens. Although the cross section is smaller by a factor of ( represents the charge of the dark matter) compared with the channel $\Psi\Psi \rightarrow XX \rightarrow \nu\nu\bar{\nu}\bar{\nu}$, the resulting secondary electrons and positrons could imprint on their spectra above GeV energies due to the reacceleration effect of cosmic ray propagation. We use the AMS-02 measurements of electrons and positrons to constrain the annihilation cross section of the channel , which rules out part of the parameter space of the large charged dark matter model to account for the muon anomaly.

生成讲解博客的中文版本

生成AI智能校验的中文版本