Physical Review D
CMS has reported indications (2.4 sigma) of the decay of the Higgs boson into mu tau. The simplest explanation for such a decay would be a general two-Higgs doublet model (2HDM). In this case, one would expect the heavy neutral Higgs bosons, H and A, to also decay in a similar manner. We study two specific models. The first is the type III 2HDM, and the second is a 2HDM, originally proposed by Branco et al., in which all flavor-changing neutral processes are given by the weak mixing matrix. In the latter model, since mixing between the second and third generations in the lepton sector is large, flavor-changing interactions are large. In this model, we find that the decays of H and A to mu tau can be as high as 60%.
Sher, M., & Thrasher, K. (2016). Flavor-changing leptonic decays of heavy Higgs bosons. Physical Review D, 93(5), 055021.