Contributions of flavor violating couplings of a Higgs boson to $pp\to WW$

Abstract

We study contributions to $pp\to W^{+}{W}^{-}\to \ell {\nu }_{\ell }{\ell }^{\prime }{\nu }_{{\ell }^{\prime }}$ in models with a new Higgs boson, $H$, and a neutral lepton, ${\nu }_4$, with couplings $H-{\nu }_4-{\nu }_{\mu }$ and $W-{\nu }_4-\mu$ through the process $pp\to H\to {\nu }_4{\nu }_{\mu }\to W\mu {\nu }_{\mu }\to \ell {\nu }_{\ell }\mu {\nu }_{\mu }$. Contrary to naive expectations, we find that contributions to $pp\to WW$ can be very large while satisfying constraints from standard $H\to WW$ and $H\to \gamma \gamma$ searches. Even the excess observed by ATLAS in $pp\to WW$, if taken at face value, can be easily accommodated. The various kinematic distributions fit nicely the experimentally determined ones. This scenario can arise for example in a two Higgs doublet model with vectorlike leptons.

Comments: 16 pages, 5 figures