The minimal fermionic model of electroweak baryogenesis

Abstract

We present the minimal model of electroweak baryogenesis induced by fermions. The model consists of an extension of the Standard Model with one electroweak singlet fermion and one pair of vector like doublet fermions with renormalizable couplings to the Higgs. A strong first order phase transition is radiatively induced by the singlet-doublet fermions, while the origin of the baryon asymmetry is due to asymmetric reflection of the same set of fermions on the expanding electroweak bubble wall. The singlet-doublet fermions are stabilized at the electroweak scale by chiral symmetries and the Higgs potential is stabilized by threshold corrections coming from a multi-TeV ultraviolet completion which does not play any significant role in the phase transition. We work in terms of background symmetry invariants and perform an analytic semiclassical calculation of the baryon asymmetry, showing that the model may effectively generate the observed baryon asymmetry for percent level values of the unique invariant CP violating phase of the singlet-doublet sector. We include a detailed study of electron electric dipole moment and electroweak precision limits, and for one typical benchmark scenario we also recast existing collider constraints, showing that the model is consistent with all current experimental data. We point out that fermion induced electroweak baryogenesis has irreducible phenomenology at the $13\text{TeV}$ LHC since the new fermions must be at the electroweak scale, have electroweak quantum numbers and couple strongly with the Higgs. The most promising searches involve topologies with multiple leptons and missing energy in the final state.

30 + 10 pages, 6 figures

References in corpus (11)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• The global electroweak fit at NNLO and prospects for the LHC and ILC
• The Sphaleron Rate in the Minimal Standard Model
• Testing Electroweak Baryogenesis with Future Colliders
• Searches for invisible decays of the Higgs boson in pp collisions at sqrt(s) = 7, 8, and 13 TeV
• The Sphaleron Rate in SU(N) Gauge Theory
• Higgs Self-Coupling as a Probe of Electroweak Phase Transition
• Dark matter and Higgs boson physics
• Four Generations, the Electroweak Phase Transition, and Supersymmetry
• Flavor Cosmology: Dynamical Yukawas in the Froggatt-Nielsen Mechanism
• CP-violation for Electroweak Baryogenesis from Dynamical CKM Matrix