Related papers: Seesaw geometry and leptogenesis
We consider the possibility of simultaneously addressing the baryon asymmetry of the Universe, the dark matter problem and the neutrino mass generation in minimal extensions of the Standard Model via sterile fermions with (small) total…
Supersymmetric thermal leptogenesis with a hierarchical right-handed neutrino mass spectrum requires the mass of the lightest right-handed neutrino to be heavier than about 10^9 GeV. This is in conflict with the upper bound on the reheating…
Leptogenesis is studied within the seesaw neutrino mass model in a regime where all sterile neutrinos have prompt rather than delayed decays. It is shown that during neutrino thermal production lepton asymmetries are generated in both…
We consider leptogenesis induced by soft supersymmetry breaking terms ("soft leptogenesis"), in the context of the inverse seesaw mechanism. In this model there are lepton number (L) conserving and L-violating soft supersymmetry-breaking…
We study constraints on neutrino properties from texture zeros in bi-large mixing See-Saw mass matrix and also from leptogenesis. Texture zeros may occur in the light (class a)) or in the heavy (class b)) neutrino mass matrices. Each of…
The bounds on the neutrino mixing angles and CP Dirac phase for an SO(10) model with lopsided mass matrices, arising from the presence of ${\bf 16}_H$ and $\bar{\bf 16}_H$ Higgs representations, are studied by variation of the one real and…
We study the thermal leptogenesis in the scenario where the standard model is extended to include one $SU(2)_{L}$ triplet Higgs boson, in addition to three generations of the right-handed neutrinos. And in the model we introduce the…
It is a common lore that in thermal leptogenesis within the type-I seesaw framework and a hierarchical spectrum of heavy right-handed neutrinos (RHNs), the CP-violating, out-of-equilibrium decay of the lightest RHN ($N_1$) is the only…
We revisit the thermal leptogenesis scenario in the type-I seesaw framework featuring three heavy Majorana neutrinos with a hierarchical mass spectrum. We focus on low energy observables, specifically the lightest neutrino mass…
In a canonical type-I seesaw scenario, the Standard Model is extended with three singlet right-handed neutrinos (RHNs) $N_i, i=1,2,3$ with masses $M_i, i=1,2,3$ to simultaneously explain sub-eV masses of light neutrinos and baryon asymmetry…
A one-flavour naturalness argument suggests that the Type I seesaw model cannot naturally explain neutrino masses and the baryon asymmetry of the Universe via hierarchical thermal leptogenesis. We prove that there is no way to avoid this…
The baryon to photon ratio in the present Universe is very accurately measured to be $(6.065 \pm 0.090) \times 10^{-10}$. We study the possible origin of this baryon asymmetry in the neutrino sector through the generic mechanism of…
Given its briefness and predictability, the minimal seesaw -- a simplified version of the canonical seesaw mechanism with only two right-handed neutrino fields -- has been studied in depth and from many perspectives, and now it is being…
We investigate the relation between non-unitarity of the leptonic mixing matrix and leptogenesis. We discuss how all parameters of the canonical type-I seesaw mechanism can, in principle, be reconstructed from the neutrino mass matrix and…
We consider the minimal supersymmetric triplet seesaw model as the origin of neutrino masses and mixing as well as of the baryon asymmetry of the Universe, which is generated through soft leptogenesis employing a CP violating phase and a…
We explore the leptonic sector of a recently proposed supersymmetric SO(10) model with supersymmetry breaking in the 3-10 TeV range. A new ingredient in this work is the requirement that the observed baryon asymmetry is explained via…
Assuming the Dirac-type neutrino masses m_D are related to quark or charged lepton masses, neutrino oscillation data indicate that right handed neutrino masses are in general strongly hierarchical. In particular, if m_D is similar to the…
We consider the seesaw mechanism of neutrino mass generation in the light of our present knowledge of the neutrino masses and mixing. We analyse the seesaw mechanism constrained by the following assumptions: (1) minimal seesaw with no Higgs…
The seesaw mechanism of neutrino mass generation is analysed under the following assumptions: (1) minimal seesaw with no Higgs triplets, (2) hierarchical Dirac masses of neutrinos, (3) large lepton mixing primarily or solely due to the…
The origin of tiny neutrino masses and the baryon number asymmetry of the Universe are naturally interpreted by the canonical seesaw and leptogenesis mechanisms, in which there are the heavy Majorana neutrino mass matrix $M_{\rm R}$, the…