Anatomy of the Real Higgs Triplet Model

Abstract

In this article, we examine the Standard Model extended by a $Y=0$ real Higgs triplet, the $\Delta$SM. It contains a $CP$-even neutral Higgs (${\Delta }^0$) and two charged Higgs bosons (${\Delta }^{\pm }$), which are quasi-degenerate in mass. We first study the theoretical constraints from vacuum stability and perturbative unitarity and then calculate the Higgs decays, including the loop-induced modes such as di-photons ($\gamma \gamma$) and $Z\gamma$. In the limit of a small mixing between the SM Higgs and ${\Delta }^0$, the latter decays dominantly to $WW$ and can have a sizable branching ratio to di-photon. The model predicts a positive definite shift in the $W$ mass, which agrees with the current global electroweak fit. At the Large Hadron Collider, it leads to a $(i)$ stau-like signature from $pp\to {\Delta }^{+}{\Delta }^{-}\to {\tau }^{+}{\tau }^{-}\nu \bar{\nu }$, $(ii)$ multi-lepton final states from $pp\to {\gamma }^{\ast }\to {\Delta }^{+}{\Delta }^{-}\to W^{+}{W}^{-}ZZ$ and $pp\to W^{\ast }\to {\Delta }^{\pm }{\Delta }^0\to W^{\pm }Z{W}^{+}{W}^{-}$ as well as $(iii)$ associated di-photon production from $pp\to W^{\ast }\to {\Delta }^{\pm }({\Delta }^0\to \gamma \gamma )$. Concerning $(i)$, the reinterpretation of the recent supersymmetric tau partner search by ATLAS and CMS excludes $m_{{\Delta }^{\pm }}<110$ GeV at 95% CL. From $(ii)$, some of the signal regions of multi-lepton searches lead to bounds close to the predicted cross-section, but electroweak scale masses are still allowed. For $(iii)$, the recast of the associated di-photon searches by ATLAS and a combined log-likelihood fit of signal and background to data find that out of the 25 signal regions, 10 provide relevant limits on Br$({\Delta }^0\to \gamma \gamma )$ at the per cent level. Interestingly, 6 signal regions show excesses at around 152 GeV, leading to a preference for a non-zero di-photon branching ratio of about 0.7% with the corresponding significance amounting to about $4\sigma$.

62 pages, 21 figures

References in corpus (39)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• An Introduction to PYTHIA 8.2
• Gauge Singlet Scalars as Cold Dark Matter
• Delta r and the W-boson mass in the Singlet Extension of the Standard Model
• Triplet Scalars and Dark Matter at the LHC
• Constraining the Natural MSSM through tunneling to color-breaking vacua at zero and non-zero temperature
• Impact of the recent measurements of the top-quark and W-boson masses on electroweak precision fits
• Measurement of the W boson mass
• Interpreting electroweak precision data including the $W$-mass CDF anomaly
• Predictions from type II see-saw mechanism in SU(5)
• Correlating $W$-Boson Mass Shift with Muon $g-2$ in the 2HDM
• Obscure Higgs boson at Colliders
• Higgs Triplets and Limits from Precision Measurements
• (Non)decoupling of the Higgs triplet effects
• On the $W$-mass and New Higgs Bosons
• Unveiling Hidden Physics at the LHC
• Anomalies in Particle Physics
• $SU(2{)}_L$ triplet scalar as the origin of the 95 GeV excess?
• W-boson mass in the triplet seesaw model
• Low-Energy Effective Theory, Unitarity, and Non-Decoupling Behavior in a Model with Heavy Higgs-Triplet Fields
• Compatibility and combination of world W-boson mass measurements
• The 2HD+a model for a combined explanation of the possible excesses in the CDF ${\mathbf{M}}_{\mathbf{W}}$ measurement and $(\mathbf{g}-2{)}_{\mu }$ with Dark Matter
• CDF $W$ boson mass and muon $g-2$ in type-X two-Higgs-doublet model with a Higgs-phobic light pseudoscalar
• $W$ boson mass shift and muon magnetic moment in the Zee model
• Compatibility of muon $g-2$, $W$ mass anomaly in type-X 2HDM
• Electroweak precision tests for triplet scalars
• Explanation of the $W$ mass shift at CDF II in the Georgi-Machacek Model
• A 95 GeV Higgs Boson in the Georgi-Machacek Model
• Kinetic Mixing, Dark Higgs Triplets, $M_W$ and All That
• Electroweak dark matter model accounting for the CDF $W$-mass anomaly
• Heavier $W$ boson, dark matter and gravitational waves from strings in an $SO(10)$ axion model
• $SU(5)$ grand unification and $W$-boson mass
• Low-mass doubly-charged Higgs bosons at LHC
• Testing the Scalar Triplet Solution to CDF's Fat $W$ Problem at the LHC
• Vacuum structure of the ${\mathbb{Z}}_2$ symmetric Georgi-Machacek model
• Minimal model for the $W$-boson mass, $(g-2{)}_{\mu }$, $h\to {\mu }^{+}{\mu }^{-}$ and quark-mixing-matrix unitarity
• Custodial Symmetry Breaking and Higgs Signatures at the LHC
• $W$ Boson Mass and Grand Unification via the Type-$\mathrm{I}\mathrm{I}$ Seesaw-like Mechanism
• Higgs Quadruplet Impact on $W$ Mass Shift, Dark Matter, and LHC Signatures

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• Multi-Lepton Probes of the Drell-Yan Production of Triplet Higgses
• Triple Higgs Production at Muon Colliders in the Higgs Triplet Model