Light Doubly Charged Higgs Boson via the $WW^*$ Channel at LHC

TL;DR

This paper investigates the potential to detect light doubly charged Higgs bosons decaying into $WW^*$ at the LHC, highlighting an unexcluded mass region and performing detailed simulations including dominant backgrounds.

Contribution

It introduces a search strategy for light $H^{\

Findings

Light $H^{\

The $H^{\\pm\\pm}$ can be observed at the 14 TeV LHC with 10-30 fb$^{-1}$.

The study includes detailed background analysis, especially non-prompt $tar{t}$.

Abstract

The doubly charged Higgs bosons $H^{\pm\pm}$ searches at the Large Hadron Collider (LHC) have been studied extensively and strong bound is available for $H^{\pm\pm}$ dominantly decaying into a pair of same-sign di-leptons. In this paper we point out that there is a large cavity in the light $H^{\pm\pm}$ mass region left unexcluded. In particular, $H^{\pm\pm}$ can dominantly decay into $WW$ or $WW^*$ (For instance, in the type-II seesaw mechanism the triplet acquires a vacuum expectation value around 1 GeV.), and then it is found that $H^{\pm\pm}$ with mass even below $2m_W$ remains untouched by the current collider searches. Searching for such a $H^{\pm\pm}$ at the LHC is the topic of this paper. We perform detailed signal and background simulation, especially including the non-prompt $t\bar{t}$ background which is the dominant one nevertheless ignored before. We show that such $H^{\pm\pm}$ should be observable at the 14 TeV LHC with 10-30 fb$^{-1}$ integrated luminosity.