Triply charged Higgs bosons at a 100\xa0TeV pp collider

Abstract

In this work, we study the potential of searching for triply charged Higgs boson originating from a complex Higgs quadruplet in the final state with at least three same-sign leptons. A detailed collider analysis of the SM backgrounds and signals is performed at a 100 TeV pp collider for the triply charged Higgs boson mass below 1 TeV and the Higgs quadruplet vacuum expectation value v_Delta ranging from 1.5times 10^{-9}~text {GeV} to 1.3~text {GeV} and the mass splitting Delta m between the nearby states of the Higgs quadruplet satisfying |Delta m|lesssim 30~text {GeV}. About 100~text {fb}^{-1} of data are required at most for 5sigma discovery. We also revisit the sensitivity at the Large Hadron Collider (LHC) and find that 5sigma discovery of the triply charged Higgs boson below 1 TeV can be reached for a relatively small v_Delta . For example, if v_Delta =10^{-6}~text {GeV} and Delta m=0, the integrated luminosity of 330~text {fb}^{-1} is needed. But for a relatively large v_Delta , i.e., v_Delta gtrsim 10^{-3}~text {GeV}, the triply charged Higgs boson above about 800 GeV cannot be discovered even in the high-luminosity LHC era. For Delta m>0, the cascade decays are open and the sensitivity can be improved depending on the value of v_Delta .