Hunting for Vectorlike Quarks

Abstract

We analyze decays of vectorlike quarks in extensions of the standard model and a two Higgs doublet model. We identify several typical patterns of branching ratios of the lightest new up-type quark, $t_4$, and down-type quark, $b_4$, depending on the structure of Yukawa couplings that mix the vectorlike and standard model quarks (we assume only mixing with the third generation) and also on their doublet or singlet nature. We find that decays into heavy neutral or charged Higgs bosons, when kinematically open, can easily dominate and even be close to 100\%: $b_4\to Hb$ at medium to large $\tan \beta$, $t_4\to Ht$ at small $\tan \beta$ and $b_4\to H^{\pm }t$, $t_4\to H^{\pm }b$ at both large and small $\tan \beta$. The pair production of vectorlike quarks leads to $6t$, $4t2b$, $2t4b$ and $6b$ final states. The decay modes into $W$, $Z$ and $h$ follow the pattern expected from the Goldstone boson equivalence limit that we generalize to scenarios with all possible couplings. We also discuss in detail the structure of Yukawa couplings required to significantly deviate from the pattern characteristic of the Goldstone boson equivalence limit that can result in essentially arbitrary branching ratios.

28 pages, 3 figures

References in corpus (6)

• Bounds and Decays of New Heavy Vector-like Top Partners
• Limits on Vectorlike Leptons from Searches for Anomalous Production of Multi-Lepton Events
• Loop Induced Single Top Partner Production and Decay at the LHC
• Prospects of searching for composite resonances at the LHC and beyond
• Shedding Light on Top Partner at the LHC
• New constraints and discovery potential for Higgs to Higgs cascade decays through vectorlike leptons

Cited by in corpus (23)

• Muon $g-2$ in two Higgs doublet models with vectorlike leptons
• Highly enhanced contributions of heavy Higgs bosons and new leptons to muon $g-2$ and prospects at future colliders
• Roadmap to explore vectorlike quarks decaying to a new scalar or pseudoscalar
• Hunting for top partner with a new signature at the LHC
• Signals with six bottom quarks for charged and neutral Higgs bosons
• Discovery prospects of a vectorlike top partner decaying to a singlet boson
• Machine learning-enhanced search for a vectorlike singlet $B$ quark decaying to a singlet scalar or pseudoscalar
• Exploring maverick top partner decays at the LHC
• Tau-jet signatures of vectorlike quark decays to heavy charged and neutral Higgs bosons
• Composite dark matter phenomenology in the presence of lighter degrees of freedom
• Optimizing Energetic Light Dark Matter Searches in Dark Matter and Neutrino Experiments
• Anatomy of Vector-Like Top-Quark Models in the Alignment Limit of the 2-Higgs Doublet Model Type-II
• Anatomy of Vector-Like Bottom-Quark Models in the Alignment Limit of the 2-Higgs Doublet Model Type-II
• Cascade decays of Heavy Higgs bosons through vectorlike quarks
• Current status on pair-produced muon-philic vectorlike leptons in multilepton channels at the LHC
• Leptonic cascade decays of a heavy Higgs boson through vectorlike leptons at the LHC
• Search for charged Higgs bosons through vector-like top quark pair production at the LHC
• Probing an MeV-Scale Scalar Boson in Association with a TeV-Scale Top-Quark Partner at the LHC
• Muon g-2 and other observables in models with extended Higgs and matter sectors
• H Marks the Spot: Searching for Exotic Production of Higgs + X to Map Out New Physics
• Impact of hidden heavy Higgs channels of VLB-Quarks below 1 TeV in 2HDM
• Multi-top signals of vectorlike quarks at the LHC
• Machine learning tagged boosted dark photon: A signature of fermionic portal matter at the LHC