Leptonic di-flavor and di-number violation processes at high energy ${{ {\boldsymbol\mu}^{\bf\pm}}{\boldsymbol\mu}^{\bf\pm}} $ colliders

Abstract：

The leptonic di-flavor violation (LFV) processes $ \mu^\pm \mu^\pm \rightarrow e^\pm e^\pm $ and $ \mu^\pm \mu^\pm \rightarrow \tau^\pm \tau^\pm $ and leptonic di-number violation (LNV) processes $ \mu^\pm \mu^\pm \rightarrow W^\pm _iW^\pm _j $ ( $ i,\;j=1,\;2 $ ) at same-sign high energy $ \mu^\pm \mu^\pm $ colliders are studied. The new physics (NP) factors that may play roles in these processes are highlighted by cataloging them into three types. Taking into account the experimental constraints, the processes at $ \mu^\pm\mu^\pm $ colliders are computed, and the results are presented properly. The results lead to the conclusion that observing the NP factors through the LFV and LNV processes at TeV-energy $ \mu^\pm\mu^\pm $ colliders has significant advantages that cannot be achieved elsewhere. Therefore, once the techniques for muon acceleration and collision are developed successfully, the option of building same-sign high energy muon colliders should be seriously considered.