Enhanced Four-Body Decays of Charged Higgs Bosons into Off-Shell Pseudoscalar Higgs and $W^{\pm }$ Boson Pairs in a Lepton-Specific 2-Higgs Doublet Model

Abstract

We study the time-honoured decay $H^{\pm }\to A{W}^{\pm }$ but for the first time, we do so for the case of both $A$ and $W^{\pm }$ being off-shell, therefore computing a $1\to 4$ body decay. We show that the corresponding decay rate not only extends the reach of $H^{\pm }$ searches to small masses of the latter but also that the results of our implementation differ significantly from the yield of the $1\to 3$ body decay over the phase space region in which the latter is normally used. We show the phenomenological relevance of this implementation in the case of the so-called lepton-specific 2-Higgs Doublet Model (2HDM) over the mass region wherein the aforementioned $1\to 4$ body decay can dominate just beyond the top (anti)quark mass. This mass region is accessible in the lepton-specific 2HDM as the Yukawa couplings are such that limits from $b\to s\gamma$ and $\tau \to \mu {\nu }_{\tau }\overline{{\nu }_{\mu }}$ observables on $M_{H^{\pm }}$ are rather mild. However, we emphasise that similar effects may occur in other 2HDM types, as the $W^{\pm }{H}^{\mp }A$ vertex is 2HDM type independent.

18 pages, 4 figures and 1 table. Updated to match with journal version

References in corpus (11)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• SuperIso v3.0: A program for calculating flavor physics observables in 2HDM and supersymmetry
• Models of Yukawa interaction in the two Higgs doublet model, and their collider phenomenology
• HiggsSignals-2: Probing new physics with precision Higgs measurements in the LHC 13 TeV era
• Basis-independent methods for the two-Higgs-doublet model III: The CP-conserving limit, custodial symmetry, and the oblique parameters S, T, U
• Search for charged Higgs bosons decaying via H+ -> tau nu in top quark pair events using pp collision data at sqrt(s) = 7 TeV with the ATLAS detector
• Search for charged Higgs bosons decaying via $H^{\pm }\to {\tau }^{\pm }\nu$ in fully hadronic final states using $pp$ collision data at $\sqrt{s}=8$ TeV with the ATLAS detector
• Search for charged Higgs bosons decaying into a top quark and a bottom quark at $\sqrt{s}$=13 TeV with the ATLAS detector
• The forgotten channels: charged Higgs boson decays to a $W^{\pm }$ and a non-SM-like Higgs boson
• Slight excess at 130 GeV in search for a charged Higgs boson decaying to a charm quark and a bottom quark at the Large Hadron Collider