相关论文: Leptogenesis in natural low-scale seesaw mechanism…
We present a purely linear seesaw mechanism in a left-right symmetric framework and then realize a novel leptogenesis scenario for parametrizing the cosmic baryon asymmetty by the charged lepton masses and the light Majorana neutrino mass…
The presently available information on neutrino oscillations can be used to tightly constrain the light neutrino mass matrix $m_\n$ under the assumption that the three known neutrinos provide explanation of the solar and atmospheric…
Heavy neutrinos with masses below the electroweak scale can simultaneously generate the light neutrino masses via the seesaw mechanism and the baryon asymmetry of the universe via leptogenesis. The requirement to explain these phenomena…
We consider low-scale leptogenesis via right-handed neutrinos $N$ coupled to a $Z'$ boson, with gauged $U(1)_{B-L}$ as a simple realization. Keeping the neutrinos sufficiently out of equilibrium puts strong bounds on the $Z'$ coupling…
Several classes of neutrino mass models, which can naturally account for hierarchical masses and the bi-large pattern of neutrino mixing, are constructed from a bottom-up perspective based on the idea of decoupling of one right-chiral…
The quasi-degeneracy of heavier sterile neutrino masses in the Neutrino Minimal Standard Model ($\nu$MSM) facilitates the production of lepton asymmetry below the electroweak scale. The first order loop corrections to this mass-difference…
Leptogenesis constitues a very simple scenario to achieve the baryon asymmetry that we observe today. It requires only the presence of right handed neutrinos (which arise very naturally in many extensions of the Standard Model) and depends…
The gravitino problem gives a severe constraint on the thermal leptogenesis scenario. This problem leads us to consider some alternatives to it if we try to keep the gravitino mass around the weak scale $m_{3/2} \sim 100$ GeV. We consider,…
We present an S$_4$ flavour symmetric model within a minimal seesaw framework resulting in mass matrices that leads to TM$_1$ mixing. Minimal seesaw is realized by adding two right-handed neutrinos to the Standard Model. The model predicts…
We present a mechanism of leptogenesis based on the out-of-equilibrium decay of a scalar particle into heavy virtual Majorana neutrinos. This scheme presents many conceptual advantages over the conventional scenario of Fukugita and…
It is known that realistic neutrino masses for neutrino oscillations may be obtained from R parity nonconserving supersymmetry. It is also known that such interactions would erase any preexisting lepton or baryon asymmetry of the Universe…
We discuss the most general necessary and sufficient condition for three massless light neutrinos in variants of the type I seesaw mechanism in which we introduce an arbitrary number of fermionic gauge singlets. We find that having massless…
In the simplest type-I seesaw leptogenesis scenario right-handed neutrino annihilation processes are absent. However, in the presence of new interactions these processes are possible and can affect the resulting $B-L$ asymmetry in an…
Lepton flavour asymmetries generated at the onset of the oscillations of sterile neutrinos with masses above the electroweak scale can be large enough to partly survive washout and to explain the baryon asymmetry of the Universe. This opens…
We propose a new leptogenesis scenario in which the lepton asymmetry and matter particles are simultaneously generated due to the coherent oscillating Higgs background. To demonstrate the possibility of our scenario, we consider the type-I…
The conventional seesaw-leptogenesis can simultaneously explain the suppression of neutrino masses and the generation of cosmic baryon asymmetry, but usually cannot predict an unambiguous relation between these two sectors. In this work we…
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…
The representation of the seesaw orthogonal matrix in the complex plane establishes a graphical correspondence between neutrino mass models and geometrical configurations, particularly useful to study relevant aspects of leptogenesis. We…
We suggest a low-scale model based on $A_4\times Z_4 \times Z_2$ symmetry and a global lepton number $U(1)_L$ symmetry capable of generating the current neutrino data. The neutrino mass smallness is reproduced by the linear seesaw…
Contrary to the common lore based on naive dimensional analysis, the seesaw scale for neutrino masses can be naturally in the TeV range, with small parameters coming from radiative corrections. We present one such class of type-I seesaw…