Abstract
We consider a singlet extension of the Standard Model (SM) with a spontaneous $Z_2$ breaking and study the gluon-gluon fusion production of the heavy scalar, with subsequent decay into a pair of SM-like Higgs bosons. We find that an on-shell interference effect can notably enhance the resonant di-Higgs production rate up to 40\%. In addition, consistently taking into account both the on-shell and off-shell interference effects between the heavy scalar and the SM di-Higgs diagrams significantly improves the HL-LHC and HE-LHC reach in this channel. As an example, within an effective field theory analysis in an explicitly $Z_2$ breaking scenario, we further discuss the potential to probe the parameter region compatible with a first order electroweak phase transition. Our analysis is applicable for general potentials of the singlet extension of the SM as well as for more general resonance searches.
Highlights
Probing the intriguing possibility of electroweak baryogenesis [1,2,3,4,5] becomes of higher relevance after the standard model (SM) Higgs boson discovery at the LHC [6,7]
IV, we study the impact of the onshell interference effect for the High Luminosity (HL)- and High Energy (HE)- LHC searches and address how a comprehensive study of the on-shell and off-shell differential cross sections would improve on their sensitivity
We focus on the novel effect of the on-shell interference contribution and discuss it in detail considering the framework of the singlet extension of the SM with spontaneous Z2 breaking
Summary
Probing the intriguing possibility of electroweak baryogenesis [1,2,3,4,5] becomes of higher relevance after the SM Higgs boson discovery at the LHC [6,7]. We shall choose the spontaneous Z2 breaking scenario of the SM plus singlet to demonstrate the importance of the novel on-shell interference effect for the resonant singlet scalar searches in the di-Higgs production mode. IV, we study the impact of the onshell interference effect for the High Luminosity (HL)- and High Energy (HE)- LHC searches and address how a comprehensive study of the on-shell and off-shell differential cross sections would improve on their sensitivity This in turn will provide the tools for a much more robust test of a strongly first-order EWPT in this type of models. The parameters in the scalar potential in Eq (2.1) can be expressed as functions of these new parameters, μ2
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
