Explaining the CMS Higgs flavor-violating decay excess

Direct searches for lepton flavor-violating Higgs boson decays in the tau mu channel have recently been reported by the CMS Collaboration. The results display a slight excess of signal events with a significance of 2.5 sigma, which translates into a branching ratio of about 1%. By interpreting these findings as a hint for beyond the standard model physics, we show that the Type-III 2HDM is capable of reproducing such a signal while at the same time satisfying from below boundedness of the scalar potential, perturbativity, electroweak precision data, measured Higgs standard decay modes, and low-energy lepton flavor-violating constraints. We have found that the allowed signal strength ranges for the b (b) over bar, WW*, and ZZ* standard channels shrink as soon as BR (h -> tau mu) similar to 1% is enforced. Thus, we point out that if the excess persists, improved measurements of these channels may be used to test our Type-III 2HDM scenario.