Light signals from a lighter Higgs

  • Patrick J. Fox
  • Neal Weiner
Open Access
Regular Article - Theoretical Physics


With the Higgs search program already quite mature, there is the exciting possibility of discovering a new particle with rates near that of the SM Higgs. We consider models with a signal in γγ below the SM Higgs mass. We discuss singlet models with additional vectorlike matter, but argue that a Type-I two Higgs doublet model can more easily provide detectable rates. In such scenarios, in regions of moderate-to-strong fermiophobia, the enhanced γγ branching ratio allows signals from V H+VBF production to yield σ × BRγγ comparable to total SM rates and would thus be detectable. Light H production can be dominated via rare top decays tbH+bW H, which provides an even more efficient means of production. We also consider this in the context of various Higgs anomalies, specifically the recent 2.9 σ (local) CMS excess at 95 GeV, the LEP Higgs excess near the same mass, and excesses in \( t\overline{t}h \) searches at Tevatron and LHC. We find regions of parameter space that can meet all simultaneously. An implication of the Type-I scenario is that any γγ excess should be associated with additional elements that could reduce background, including b-jets, forward jets or signs of vector boson production.


Beyond Standard Model Higgs Physics 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Theoretical Physics DepartmentFermilabBataviaU.S.A.
  2. 2.Center for Cosmology and Particle Physics, Department of PhysicsNew York UniversityNew YorkUSA
  3. 3.Center for Computational Astrophysics, Flatiron InstituteNew YorkU.S.A.

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