$\nu$ Electroweak Baryogenesis: The Scalar Singlet Strikes Back

Abstract

We perform a thorough scan of the parameter space of a general singlet scalar extension of the Standard Model to identify the regions which can lead to a strong first-order phase transition, as required by the electroweak baryogenesis mechanism. We find that taking into account bubble nucleation is a fundamental constraint on the parameter space and present a conservative and fast estimate for it to enable efficient parameter space scanning. The allowed regions turn out to be already significantly probed by constraints on the scalar mixing from Higgs signal strength measurements. We also consider the addition of new neutrino singlet fields with Yukawa couplings to both scalars and forming heavy (pseudo)-Dirac pairs, as in the linear or inverse see-saw mechanisms for neutrino mass generation. Interestingly, we identify an interplay between the strength of the phase transition and the stability of the electroweak vacuum which prevents these Yukawa couplings to become arbitrarily large. Thus, their inclusion does not alter the early universe phenomenology or allowed parameter space in a significant way. Conversely, we find allowed regions of the parameter space where the presence of the neutrino singlets would remarkably modify the collider phenomenology, yielding interesting new signatures in Higgs and singlet scalar decays.

Matches published version. Scatter plots scanning the parameter space with many more statistics

References in corpus (26)

• Singlet Higgs Phenomenology and the Electroweak Phase Transition
• Right-Handed Neutrinos at LHC and the Mechanism of Neutrino Mass Generation
• A portrait of the Higgs boson by the CMS experiment ten years after the discovery
• A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery
• Low energy effects of neutrino masses
• Status of the Higgs Singlet Extension of the Standard Model after LHC Run 1
• Singlet-Catalyzed Electroweak Phase Transitions and Precision Higgs Studies
• Dynamics of Electroweak Phase Transition In Singlet-Scalar Extension of the Standard Model
• Neutrino Jets from High-Mass $W_R$ Gauge Bosons in TeV-Scale Left-Right Symmetric Models
• Gravitational waves and Higgs boson couplings for exploring first order phase transition in the model with a singlet scalar field
• The Higgs Vacuum Uplifted: Revisiting the Electroweak Phase Transition with a Second Higgs Doublet
• Improved sphaleron decoupling condition and the Higgs coupling constants in the real singlet-extended SM
• Dimensional reduction of the Standard Model coupled to a new singlet scalar field
• Ultra-relativistic bubbles from the simplest Higgs portal and their cosmological consequences
• Electroweak Phase Transition and LHC Signatures in the Singlet Majoron Model
• Combining thermal resummation and gauge invariance for electroweak phase transition
• The NuTeV Anomaly, Lepton Universality, and Non-Universal Neutrino-Gauge Couplings
• Probing electroweak phase transition with multi-TeV muon colliders and gravitational waves
• Enhancing Dark Matter Annihilation into Neutrinos
• Dark Matter Through the Neutrino Portal
• Semi-analytic techniques for calculating bubble wall profiles
• The NuTeV Anomaly, Neutrino Mixing, and a Heavy Higgs Boson
• Experimental Constraints on Higgs Boson Decays to TeV-scale Right-Handed Neutrinos
• Automated Neutrino Jet and Top Jet Predictions at Next-to-Leading-Order with Parton Shower Matching in Effective Left-Right Symmetric Models
• HNL mass degeneracy: implications for low-scale seesaws, LNV at colliders and leptogenesis
• BSM $\nu$ physics: complementarity across energies -- a white paper for Snowmass 2021

Cited by in corpus (2)

• Investigating the Electroweak Phase Transition with a Real Scalar Singlet at a Muon Collider
• Sterile neutrino Dark Matter in the minimal Dirac Seesaw