Hybrid dynamical electroweak symmetry breaking with heavy quarks and the 125 GeV Higgs

Abstract

Existing models of dynamical electroweak symmetry breaking (EWSB) find it very difficult to get a Higgs of mass lighter than $m_t$. Consequently, in light of the LHC discovery of the ~125 GeV Higgs, such models face a significant obstacle. Moreover, with three generations those models have a superheavy cut-off around $10^{17}$ GeV, requiring a significant fine-tuning. To overcome these twin difficulties, we propose a hybrid framework for EWSB, in which the Higgs mechanism is combined with a Nambu-Jona-Lasinio mechanism. The model introduces a strongly coupled doublet of heavy quarks with a mass around 500 GeV, which forms a condensate at a compositeness scale $\Lambda$ about a few TeV, and an additional unconstrained scalar doublet which behaves as a "fundamental" doublet at $\Lambda$. This "fundamental"-like doublet has a vanishing quartic term at $\Lambda$ and is, therefore, not the SM doublet, but should rather be viewed as a pseudo-Goldstone boson of the underlying strong dynamics. This setup is matched at the compositeness scale $\Lambda$ to a tightly constrained hybrid two Higgs doublet model, where both the composite and unconstrained scalars participate in EWSB. This allows us to get a good candidate for the recently observed 125 GeV scalar which has properties very similar to the Standard Model Higgs. The heavier (mostly composite) CP-even scalar has a mass around 500 GeV, while the pseudoscalar and the charged Higgs particles have masses in the range 200 -300 GeV.

latex, 8 pages, 4 figures. V3: references added, a new section on Higgs signals added, figures updated, abstract and introduction revised

References in corpus (14)

• 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
• Light custodians in natural composite Higgs models
• Light Kaluza-Klein States in Randall-Sundrum Models with Custodial SU(2)
• The discovery of the fourth family at the LHC: what if?
• LHC Signatures of Two-Higgs-Doublets with Fourth Family
• Electroweak Symmetry Breaking from a Holographic Fourth Generation
• Search for pair production of heavy top-like quarks decaying to a high-pT W boson and a b quark in the lepton plus jets final state at sqrt(s)=7 TeV with the ATLAS detector
• Pseudoscalar Higgs Bosons at the LHC: Production and Decays into Electroweak Gauge Bosons Revisited
• New Strongly Coupled Sector at the Tevatron and the LHC
• The Fourth Generation t-prime in Extensions of the Standard Model
• Top-quark and neutrino composite Higgs bosons
• Electroweak Constraints on the Fourth Generation at Two Loop Order
• Dynamical symmetry breaking, CP violation, and a Higgs-like particle

Cited by in corpus (7)

• Baryogenesis in the two doublet and inert singlet extension of the Standard Model
• Delta r in the Two-Higgs-Doublet Model at full one loop level -- and beyond
• A Composite Higgs Model with Minimal Fine-Tuning I.~The Large-N and Weak-technicolor Limit
• Chiral heavy fermions in a two Higgs doublet model: 750 GeV resonance or not
• Is the Higgs Boson Composed of Neutrinos?
• Dynamical Origin of the Electroweak Scale and the 125 GeV Scalar
• Top condensation model: a step towards the correct prediction of the Higgs mass