Explaining muon magnetic moment and AMS-02 positron excess in a gauged horizontal symmetric model

摘要

We extended the standard model with a fourth generation of fermions toexplain the discrepancy in the muon magnetic moment and to describe thepositron excess observed by AMS-02 experiment. We introduce a gauged$SU(2)_{HV}$ horizontal symmetry between the muon and the 4th generation leptonfamilies and identified the 4th generation right-handed neutrino as the darkmatter with mass $\sim 700$ GeV. The dark matter annihilates through$SU(2)_{HV}$ gauge boson into final states $(\mu^+ \mu^-)$ and $(\nu^c_\mu~\nu_\mu)$. The $SU(2)_{HV}$ gauge boson with mass $\sim 1.4$ TeV gives therequired contribution to the muon $(g-2)$ and satisfy the experimentalconstraint from BNL measurement.