Related papers: Hot Leptogenesis
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…
Supersymmetric scenarios where the lightest superparticle (LSP) is the gravitino are an attractive alternative to the widely studied case of a neutralino LSP. A strong motivation for a gravitino LSP arises from the possibility of achieving…
The mechanism of thermal leptogenesis is investigated in the high-energy regime of braneworld cosmology. Within the simplest seesaw framework with hierarchical heavy Majorana neutrinos, we study the implications of the modified Friedmann…
After a brief discussion of baryon and lepton number nonconservation, we review the status of thermal leptogenesis with GUT scale neutrino masses, as well as low scale alternatives with keV neutrinos as dark matter and heavy neutrino masses…
We present a systematic study of leptogenesis in neutrino mass models with $\mu\tau$-flavoured CP symmetry. In addition to the strong hierarchical $N_1$-dominated scenario ($N_1$DS) in the `two flavour regime' of leptogenesis, we show that…
It has been proposed that in a part of the parameter space of the Standard Model completed by three generations of keV...GeV right-handed neutrinos, neutrino masses, dark matter, and baryon asymmetry can be accounted for simultaneously.…
Leptogenesis, i.e. the creation of a lepton asymmetry in the early Universe, may occur through the decay of heavy singlet (right-handed) neutrinos. If we require it not to be erased by physics beyond the Standard Model at the TeV energy…
We make a simple observation that if one of the right-chiral neutrinos is very heavy or its Yukawa couplings to the standard lepton doublets are negligible, so that it effectively decouples from the see-saw mechanism, the prediction for the…
We propose a novel leptogenesis scenario at the reheating era. Our setup is minimal in the sense that, in addition to the standard model Lagrangian, we only consider an inflaton and higher dimensional operators. The lepton number asymmetry…
We propose a scenario of thermal leptogenesis at the TeV scale in the context of an extension of the Standard Model with 4 generations. We also add one right-handed Majorana neutrino for each generation to generate left handed neutrino…
We review the current status of the leptogenesis scenario originally proposed by Akhmedov, Rubakov and Smirnov (ARS). It takes place in the parametric regime where the right-handed neutrinos are at the electroweak scale or below and the…
Heavy right handed neutrinos could not only explain the observed neutrino masses via the seesaw mechanism, but also generate the baryon asymmetry of the universe via leptogenesis due to their CP-violating interactions in the early universe.…
Recent years have seen a great improvement in the computation of $CP$-conserving and $CP$-violating equilibration rates for leptogenesis. These are relevant for the relativistic regime of the sterile Majorana fermions and the dynamics of…
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…
During the process of thermal leptogenesis temperature decreases by about one order of magnitude while the baryon asymmetry is generated. We present an analytical description of this process so that the dependence on the neutrino mass…
The production rate of right-handed neutrinos from a Standard Model plasma at a temperature above a hundred GeV is evaluated up to NLO in Standard Model couplings. The results apply in the so-called relativistic regime, referring…
We study the scenario of thermal leptogenesis in which the leptonic asymmetries are resonantly enhanced through the mixing of nearly degenerate heavy Majorana neutrinos that have mass differences comparable to their decay widths.…
The production rate of right-handed neutrinos from a Standard Model plasma at a temperature above a hundred GeV has previously been evaluated up to NLO in Standard Model couplings (g ~ 2/3) in relativistic (M ~ pi T) and non-relativistic…
We show that by adding to the standard model plus the type I seesaw different types of scalars, it is possible to construct models that satisfy the three requirements of (i) generating neutrino masses at the TeV scale, (ii) being testable…
In realistic unified models involving an $SO(10)$-like pattern of Dirac and heavy right-handed (RH) neutrino masses, the lightest right-handed neutrino $N_1$ is too light to yield successful thermal leptogenesis, barring highly fine tuned…