Related papers: Revisiting the Minimal Nelson-Barr Model
Formation of transitory domain walls is quite generic in theories with spontaneous breaking of discrete symmetries. Since these walls are in conflict with cosmology, there has to be some mechanism which makes them disappear. We study one…
We present a general description of the problems encountered when attempting to build a simple model of leptogenesis and hence of baryogenesis at an energy scale as low as 1-10 TeV. We consider three possible lepton asymmetry enhancement…
We study the scenario of baryogenesis through leptogenesis in higher-dimensional theories, in which the scale of quantum gravity is many orders of magnitude smaller than the usual Planck mass. The minimal realization of these theories…
We consider a minimal extension of the Standard Model with one singlet neutrino per generation that can realize resonant leptogenesis at the electroweak scale. In particular, the baryon asymmetry in the Universe can be created by resonant…
I suggest an extension of the SM by introducing a dark sector with the local $U(1)_{D}$ symmetry. The particles in the dark sector bring about the new physics beyond the SM. In particular the global $B-L$ symmetry is violated just above the…
We analyze leptogenesis in the context of seesaw models with almost conserved lepton number, focusing on the L-conserving contribution to the flavoured CP asymmetries. We find that, contrary to previous claims, successful leptogenesis is…
Seesaw models with a slightly broken lepton number symmetry can explain small neutrino masses, and allow for low-scale leptogenesis. We make a thorough analysis of leptogenesis within the simplest model with two right-handed (RH) neutrinos…
One class of solutions to the strong CP problem relies on generalized parity symmetries. A minimal model of this type, constructed by Babu and Mohapatra and based on a softly broken parity symmetry, has the remarkable property that…
We propose a minimal extension of the type-I seesaw model to realise leptogenesis from the co-annihilation of dark sector particles. The type-I seesaw model is extended with a singlet fermion and two singlet scalars charged under a $Z_{2}$…
We consider a question which curiously had not been properly considered so far: in the standard seesaw model what is the minimum value the mass of a right-handed (RH) neutrino must have for allowing successful leptogenesis via CP-violating…
It has been known for some time that asymptotic parity invariance of weak interactions can provide a solution to the strong CP problem without the need for the axion. Left-right symmetric theories which employ a minimal Higgs sector…
We consider leptogenesis in a left-right-symmetric seesaw scenario in which neutrino mass generation and leptogenesis are dominated by the type-II seesaw term. Motivated by grand unification, we assume that the neutrino Dirac mass matrix is…
The paper presents a new reduction method designed for dynamic contact problems. Recently, we have proposed an efficient reduction scheme for the node-to-node formulation, that leads to Linear Complementarity Problems (LCP). Here, we…
The presence of domain walls separating regions of unbroken $SU(2)_L$ and $SU(2)_R$ is shown to provide necessary conditions for leptogenesis which converts later to the observed Baryon aymmetry. The strength of lepton number violation is…
We discuss leptogenesis in a realistic supersymmetric model of inflation with a low reheat temperature 1-10 GeV. The lepton asymmetry is generated by a decaying right handed sneutrino, which is produced after inflation during preheating.…
The physics of electroweak baryogenesis is described with the aim of making the essentials clear to non-experts. Several models for the source of the necessary CP violation are discussed: CKM phases as in the minimal standard model, general…
We revisit the generation of a matter-antimatter asymmetry in the minimal extension of the Standard Model with two singlet heavy neutral leptons (HNL) that can explain neutrino masses. We derive an accurate analytical approximation to the…
We propose a simple renormalizable model for the spontaneous CP violation based on $SU(2)_{L}\times U(1)_{Y}\times A_{4}$ symmetry in a radiative seesaw mechanism, which can be guaranteed by an extra $Z_{2}$ symmetry. In our model CP is…
The CP-violation necessary for the generation of the baryon asymmetry of the Universe in the "flavoured" leptogenesis scenario can arise from the "low energy" PMNS neutrino mixing matrix and/or from the "high energy" part of neutrino Yukawa…
A typical problem of the leptogenesis scenario is the mismatch between the maximum reheat temperature implied by gravitino overproduction bound and the minimum temperature required to create thermally the lightest right-handed neutrino. We…