Custodial Symmetry Breaking and Higgs Signatures at the LHC

Abstract

We discuss the simplest model that predicts a tree level modification of the $\rho$ parameter from a shift in the $W$-mass without changing the prediction for the $Z$ mass. This model predicts a new neutral Higgs and two charged Higgses, with very similar masses and suppressed couplings to the Standard Model fermions. We discuss the decay properties of these new scalar bosons, and the main signatures at the Large Hadron Collider. Comparing these signatures for the first time to the latest measurements, we show that while masses around 200 GeV are excluded for some scenarios, over a wide range of model parameter space the new bosons can have a mass close to the electroweak scale without violating existing limits from experimental searches or destroying the agreement with measurements. We investigate the scenario where the new neutral Higgs is fermiophobic and has a large branching ratio into $W$ gauge bosons and/or photons, and show that this could lead to a signal in the diphoton mass spectrum at low Higgs masses. We discuss the different signatures that can motivate new measurements and searches at the Large Hadron Collider.

arXiv commentsome corrections, extra discussion, references added, conclusions unchanged, version to appear in Physical Review D

References in corpus (44)

• 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
• FeynRules 2.0 - A complete toolbox for tree-level phenomenology
• MadGraph 5 : Going Beyond
• UFO - The Universal FeynRules Output
• Herwig 7.0 / Herwig++ 3.0 Release Note
• Event Generation with Sherpa 2.2
• The CP-conserving two-Higgs-doublet model: the approach to the decoupling limit
• Observation of a new boson with mass near 125 GeV in pp collisions at sqrt(s) = 7 and 8 TeV
• Robust Independent Validation of Experiment and Theory: Rivet version 3
• Stability and Symmetry Breaking in the General Two-Higgs-Doublet Model
• Search for Scalar Diphoton Resonances in the Mass Range $65-600$ GeV with the ATLAS Detector in $pp$ Collision Data at $\sqrt{s}$ = 8 $TeV$
• Search for a light charged Higgs boson in top quark decays in pp collisions at sqrt(s) = 7 TeV
• Triplet Scalars and Dark Matter at the LHC
• Search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV in the diphoton final state in proton-proton collisions at $\sqrt{s}=$ 8 and 13 TeV
• Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at $\sqrt{s}=8$ TeV with ATLAS
• Precision observables in SU(2) x U(1) models with an additional Higgs triplet
• Measurements of Higgs boson production cross sections and couplings in the diphoton decay channel at $\sqrt{s}=$ 13 TeV
• Search for heavy resonances decaying into a pair of $Z$ bosons in the ${\ell }^{+}{\ell }^{-}{\ell }^{\prime +}{\ell }^{\prime -}$ and ${\ell }^{+}{\ell }^{-}\nu \bar{\nu }$ final states using 139 fb${}^{-1}$ of proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Measurements of $Z\gamma$ and $Z\gamma \gamma$ production in $pp$ collisions at $\sqrt{s}=$ 8 TeV with the ATLAS detector
• Measurement of fiducial and differential $W^{+}{W}^{-}$ production cross-sections at $\sqrt{s}=$13 TeV with the ATLAS detector
• (Non)decoupling of the Higgs triplet effects
• Higgs Triplets and Limits from Precision Measurements
• On the $W$-mass and New Higgs Bosons
• Constraining new physics with collider measurements of Standard Model signatures
• Measurement of the properties of Higgs boson production at $\sqrt{s}=13$ TeV in the $H\to \gamma \gamma$ channel using $139$ fb${}^{-1}$ of $pp$ collision data with the ATLAS experiment
• Higgs mass bounds in a Triplet Model
• Mass bounds in a model with a Triplet Higgs
• $SU(2{)}_L$ triplet scalar as the origin of the 95 GeV excess?
• Testing new physics models with global comparisons to collider measurements: the Contur toolkit
• Measurements of differential cross-sections in four-lepton events in 13 TeV proton-proton collisions with the ATLAS detector
• Collider Probes of Real Triplet Scalar Dark Matter
• Low-Energy Effective Theory, Unitarity, and Non-Decoupling Behavior in a Model with Heavy Higgs-Triplet Fields
• Measurement of the production cross section of three isolated photons in $pp$ collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector
• Measurement of the $Z\gamma \to \nu \bar{\nu }\gamma$ production cross section in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector and limits on anomalous triple gauge-boson couplings
• Electroweak precision tests for triplet scalars
• Double fermiophobic Higgs boson production at the LHC and LC
• Measurement of the production cross section of pairs of isolated photons in $pp$ collisions at 13 TeV with the ATLAS detector
• Search for direct pair production of supersymmetric partners of $\tau$ leptons in the final state with two hadronically decaying $\tau$ leptons and missing transverse momentum in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Diphoton and Diboson Probes of Fermiophobic Higgs Bosons at the LHC
• Multi-photon signatures at the Fermilab Tevatron
• Measurement of $Z\gamma \gamma$ production in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for resonant $WZ\to \ell \nu {\ell }^{\prime }{\ell }^{\prime }$ production in proton$-$proton collisions at $\sqrt{\mathbf{s}}=13$ TeV with the ATLAS detector
• Measurement of the top quark branching ratios into channels with leptons and quarks with the ATLAS detector

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• Vector dark matter and LHC constraints, including a 95 GeV light Higgs boson
• Anatomy of the Real Higgs Triplet Model
• LHC Signatures of the Generic Georgi-Machacek Model
• Constraining off-shell Higgs boson production and the Higgs boson total width using $WW\to \ell \nu \ell \nu$ final states with the ATLAS detector
• Multi-Lepton Probes of the Drell-Yan Production of Triplet Higgses