Abstract
In several searches for additional Higgs bosons at the LHC, in particular in a CMS search exploring decays to pairs of top quarks, tbar{t}, and in an ATLAS search studying tau leptons, tau ^+tau ^-, local excesses of about 3,sigma standard deviations or above have been observed at a mass scale of approximately 400 ,text {GeV}. We investigate to what extent a possible signal in these channels could be accommodated in the Next-to-Two-Higgs-Doublet Model (N2HDM) or the Next-to Minimal Supersymmetric Standard Model (NMSSM). In a second step we analyze whether such a model could be compatible with both a signal at around 400,text {GeV} and 96,text {GeV}, where the latter possibility is motivated by observed excesses in searches for the b bar{b} final state at LEP and the di-photon final state at CMS. The analysis for the N2HDM reveals that the observed excesses at 400 ,text {GeV} in the tbar{t} and tau ^+tau ^- channels point towards different regions of the parameter space, while one such excess and an additional Higgs boson at around 96,text {GeV} could simultaneously be accommodated. In the context of the NMSSM an experimental confirmation of a signal in the tbar{t} final state would favour the alignment-without-decoupling limit of the model, where the Higgs boson at 125,text {GeV} could be essentially indistinguishable from the Higgs boson of the standard model. In contrast, a signal in the tau ^+tau ^- channel can only be accommodated outside of this limit, and parts of the investigated parameter space could be probed with Higgs signal-rate measurements at the (HL-)LHC.
Highlights
In the year 2012 the ATLAS and CMS Collaborations have discovered a new particle with a mass of about 125 GeV [1– 3]
We investigate to what extent a possible signal in these channels could be accommodated in the Next-to-Two-Higgs-Doublet Model (N2HDM) or the Nextto Minimal Supersymmetric Standard Model (NMSSM)
Within the current experimental and theoretical uncertainties the properties of this particle, which in the following is denoted as h125, agree with the predictions for the Higgs boson of the Standard Model (SM) of particle physics, but they are compatible with the interpretation as a Higgs boson in a variety of SM extensions corresponding to different underlying physics
Summary
In the year 2012 the ATLAS and CMS Collaborations have discovered a new particle with a mass of about 125 GeV [1– 3]. In our investigation in this paper we will perform a χ 2 analysis taking into account the observed excesses in the pp → A → ttchannel at CMS and the pp → φ → τ +τ − channel at ATLAS, since in both cases the observed excesses over the background expectation are not in direct tension with corresponding results (in terms of search channel and integrated luminosity) from the other collaboration. We demonstrate that the NMSSM can fit each of the excesses at 400 GeV individually, while complying with the BSM Higgs-boson searches and the signal-rate measurements of the Higgs boson at 125 GeV In this analysis, we show that a well motivated parameter region to accommodate the ttexcess is given by the alignmentwithout-decoupling limit of the NMSSM [30]. In the Appendix we provide supplementary material on different Yukawa types of the N2HDM and a discussion of the constraints from the signal at 125 GeV in the alignment-without-decoupling limit of the NMSSM
Sign-in/Register to view highlights & summary 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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
