相关论文: Nonzero U_{e3}, CP violation and leptogenesis in a…

We study the interplay between flavor symmetries and leptogenesis in the case when the scale of flavor symmetry breaking is higher than the scale at which lepton number is violated. We show that when the heavy Majorana neutrinos belong to…

We propose a new scenario for baryogenesis through leptogenesis, where the CP phase relevant for leptogenesis is connected directly to the PMNS phase(s) in the light neutrino mixing matrix. The scenario is realized in case only one CP phase…

The symmetry breaking of left right symmetric model around few TeV range permits the existence of massive right handed neutrinos or gauge bosons. In this work the decay of lightest right handed neutrinos in a class of minimal left right…

By demanding a compact spectrum for the right-handed neutrinos and an approximate quark-lepton symmetry inspired from SO(10) gauge unification (assuming a Dirac neutrino mass matrix close to the up quark mass matrix), we construct a {\it…

We construct an extension of the supersymmetric standard model where both CP symmetry and R-parity are spontaneously broken. We study the electroweak symmetry breaking sector of the model and find minima consistent with the experimental…

Baryogenesis appears to require lepton number violation. This is naturally realized in extensions of the standard model containing right-handed neutrinos. We discuss the generation of a baryon asymmetry by the out-of-equilibrium decay of…

Flavor effects due to lepton interactions in the early Universe may have played an important role in the generation of the cosmological baryon asymmetry through leptogenesis. If the only source of high-energy CP violation comes from the…

The simplest neutrino mass models based on $A_4$ symmetry predict $\theta_{13} = 0$ at tree level, a value that contradicts recent data. We study models that arise from the spontaneous breaking of an $SO(3)$ symmetry to its $A_4$ subgroup,…

Recent developments in thermal leptogenesis are reviewed. Neutrino mixing data favor a simple picture where the matter-anti matter asymmetry is generated by the decays of the heavy RH neutrinos mildly close to thermal equilibrium and,…

We discuss the possible origin of non-zero reactor mixing angle $\theta_{13}$ and Dirac CP phase $\delta_{CP}$ in the leptonic sector from a combination of type I and type II seesaw mechanisms. Type I seesaw contribution to neutrino mass…

Leptogenesis is an attractive scenario in which neutrino masses and baryon asymmetry of the Universe are explained together under a minimal set of assumptions. After formulating the problem of initial conditions and introducing the strong…

We study the lepton sector in the model based on the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ which do not contain particles with exotic electric charges. The seesaw mechanism and discrete $A_4$ symmetry are introduced into…

We consider a model with three right-handed neutrinos in which Yukawa coupling constants and Majorana masses are obtained by requiring the modular $A_4$ symmetry. It has been shown that the model can explain mass hierarchies and mixing…

We make an attempt to study neutrino phenomenology in the framework of type-III seesaw by considering $A_4$ modular symmetry in the super-symmetric context. In addition, we have included a local $U(1)_{B-L}$ symmetry which eventually helps…

We present a simple extension of the Standard Model with three right-handed neutrinos in a SUSY framework, with an additional U(1$)_\text{F}$ abelian flavor symmetry with a non standard leptonic charge $L_e-L_\mu-L_\tau$ for lepton doublets…

We propose a new mechanism of baryogenesis which proceeds via a CP-violating phase transition. During this phase transition, the coupling of the Weinberg operator is dynamically realised and subsequently a lepton asymmetry is generated via…

We study in detail the mechanism of baryon and lepton asymmetry generation in the framework of the $\nu$MSM (an extension of the Standard Model by three singlet fermions with masses smaller than the electroweak scale). We elucidate the…

We explore low-scale leptogenesis in a class of supersymmetric SO(10) models using extra singlet neutrinos and the Higgs representations {126}_H\oplus {\ovl{126}}_H as well as {16}_H \oplus {\bar {16}}_H. A singlet neutrino, which can be as…

The minimal gauged U(1)$_{L_\mu-L_\tau}$ model is a simple extension of the Standard Model and has a strong predictive power for the neutrino sector. In particular, the mass spectrum and couplings of heavy right-handed neutrinos are…

If the baryon asymmetry of the Universe is produced by leptogenesis, CP violation is required in the lepton sector. In the seesaw extension of the Standard Model with three hierarchical right-handed neutrinos, we show that the baryon…