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

TL;DR

This paper explores how flavor-violating couplings of a new Higgs boson can significantly contribute to $pp o WW$ processes, potentially explaining observed excesses while remaining consistent with existing constraints.

Contribution

It demonstrates that flavor-violating Higgs couplings can produce large $pp o WW$ signals, offering a novel explanation for experimental excesses within certain models.

Findings

Large contributions to $pp o WW$ are possible despite existing constraints.

The scenario can explain the ATLAS $WW$ excess.

Kinematic distributions match experimental data well.

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.