Related papers: Assessing Perturbativity and Vacuum Stability in H…
In the so-called "Yukawaon" model, the (effective) Yukawa coupling constants $Y_f^{eff}$ are given by vacuum expectation values (VEVs) of scalars $Y_f$ (Yukawaons) with $3\times 3$ components. In this brief report, we change VEV forms…
Both neutrinoless double beta decay and leptogenesis require neutrinos to be Majorana fermions. A relation between these two phenomena can be derived once the mechanism of neutrino mass generation is specified. We first derive the…
Scale invariance may be a classical symmetry which is broken radiatively. This provides a simple way to stabilise the scale of electroweak symmetry breaking against radiative corrections. But for such a theory to be fully realistic, it must…
We discuss leptogenesis constraints on the mass of the right-handed $W$-boson ($W_R$) in a TeV-scale Left-Right seesaw model (LRSM) for neutrino masses. For generic Dirac mass of the neutrinos, i.e. with all Yukawa couplings $\lesssim…
Type-II seesaw is a simple scenario in which Majorana neutrino masses are generated by the exchange of a heavy scalar electroweak triplet. When endowed with additional heavy fields, such as right-handed neutrinos or extra triplets, it also…
The temperature-dependent mass of the heavy neutrino can lead to the second leptogenesis occurring below the electroweak scale, potentially explaining the large discrepancy between baryon and lepton asymmetries. We investigate this scenario…
We have explored an extended seesaw model accommodating a keV sterile neutrino adopting $U(1)_{B-L}$ symmetry. This model provides a natural platform for achieving resonant leptogenesis to account for the observed baryon asymmetry of the…
In this paper, we investigate leptogenesis under the neutrino mass anarchy hypothesis in both type-I and type-II seesaw models. We first revisit the corresponding study in the type-I seesaw framework with two improvements: in contrast to…
General issues in the renormalization group evolution of fermion masses and mixings is discussed. An effective fixed point in the top quark Yukawa coupling can strongly constrain its value at the electroweak scale. Predictions following…
It is shown that the requirement of preservation of baryon asymmetry does not rule out a scale for leptogenesis as low as 10 TeV. The conclusions are compatible with see-saw mechanism if for example the pivot mass scale for neutrinos is…
We investigate low-scale resonant leptogenesis in an $SU(5) \times \mathcal{T}_{13}$ model where a single high energy phase in the complex Tribimaximal seesaw mixing produces the yet-to-be-observed low energy Dirac and Majorana ${CP}$…
We systematically investigate constraints on the parameters of the supersymmetric type-I seesaw mechanism from the requirement of successful thermal leptogenesis in the presence of upper bounds on the reheat temperature $T_\mathrm{RH}$ of…
We consider the Standard Model extended by right-handed neutrinos to explain massive neutrinos through the seesaw mechanism. The new fermion can be observed when it has a sufficiently small mass and large mixings to left-handed neutrinos.…
We discuss the thermal leptogenesis mechanism within the minimal gauged U(1)$_{L_\mu-L_\tau}$ model to explain the observed baryon asymmetry of the Universe (BAU). In such framework, the phases of the Pontecorvo-Maki-Nakagawa-Sakata…
Motivated by the fact that the Dirac phase in the PMNS matrix is the only CP-violating parameter in the leptonic sector that can be measured in neutrino oscillation experiments, we examine the possibility that it is the dominant source of…
We revisit the production of leptonic asymmetries in minimal extensions of the Standard Model that can explain neutrino masses, involving extra singlets with Majorana masses in the GeV scale. We study the quantum kinetic equations both…
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…
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.…
We analyse the implications of right-handed neutrinos on the stability of the electroweak vacuum in two-Higgs-doublet models with supersymmetry at high scale. It is assumed that supersymmetry is broken at scale $M_S = 2 \times 10^{16}$ GeV…
We propose a new mechanism for leptogenesis, which is naturally realized in some models with a flavor symmetry based on the discrete group A_4, where the symmetry breaking parameter also controls the Majorana masses for the heavy right…