相关论文: Lepton asymmetry from mixing and oscillations
We describe mixing scalar particles and Majorana fermions using Closed-Time-Path methods. From the Kadanoff-Baym equations, we obtain the charge asymmetry, that is generated from decays and inverse decays of the mixing particles. Within one…
Thermal leptogenesis explains the observed matter-antimatter asymmetry of the universe in terms of neutrino masses, consistent with neutrino oscillation experiments. We present a full quantum mechanical calculation of the generated lepton…
Flavour models may display a relation between the CP-violating asymmetry for leptogenesis and low-energy parameters. If the flavour symmetry produces an exact mass independent lepton mixing scheme at leading order (with type I see-saw) the…
We extend to the highly degenerate case a recent approach for analyzing the sources of CP violation in baryogenesis models with quasi-degenerate neutrinos. In this approach an expansion of the resummed propagator around the poles is plugged…
Thermal leptogenesis explains the observed matter-antimatter asymmetry of the universe in terms of neutrino masses, consistent with neutrino oscillation experiments. We present a full quantum mechanical calculation of the generated lepton…
We describe a loopwise perturbative truncation scheme for quantum transport equations in the Kadanoff-Baym formalism, which does not necessitate the use of the so-called Kadanoff-Baym or quasi-particle ansaetze for dressed propagators. This…
Solving the Kadanoff-Baym (KB) equations in a different method from our previous analysis, we obtain the CP violating parameter $\varepsilon$ in the thermal resonant leptogenesis without assuming smallness of the off-diagonal Yukawa…
Flavour effects play an important role in the statistical evolution of particle number densities in several particle physics phenomena. We present a fully flavour-covariant formalism for transport phenomena, in order to consistently capture…
The lepton asymmetry generated by the out-of-equilibrium decays of heavy Majorana neutrinos with a quasi-degenerate mass spectrum is resonantly enhanced. In this work, we study this scenario within a first-principle approach. The quantum…
The generation of a baryon asymmetry via leptogenesis is usually studied by means of classical kinetic equations whose applicability to processes in the hot and expanding early universe is questionable. The approximations implied by the…
We study the sources of CP violation for baryogenesis models with quasi-degenerate neutrinos. Our approach is to use the renormalized propagator in a quantum field theory model of neutrino oscillations, paying close attention to unitarity…
A novel contribution to the leptonic CP asymmetries in type II seesaw leptogenesis scenarios is obtained for the cases in which flavor effects are relevant for the dynamics of leptogenesis. In the so-called flavoured leptogenesis regime,…
We present a low-scale type-I seesaw scenario with discrete flavor and CP symmetries. This scenario not only explains the measured values of the lepton mixing angles, but also makes predictions for leptonic CP violation, and connects the…
Cyclic symmetry in the neutrino sector with the type-I seesaw mechanism in the mass basis of charged leptons and right chiral neutrinos ($N_{iR}$, $i=e,\mu,\tau$) generates two fold degenerate light neutrino and three fold degenerate heavy…
We study the implications for generating the cosmological baryon asymmetry through leptogenesis in the recent model of Fileviez Perez and Wise, which provides a new mechanism for generating neutrino masses at one-loop by introducing new…
We analyze the interplay between leptogenesis and residual symmetry in the framework of two right-handed neutrino model. Working in the flavor basis, we show that all the leptogenesis CP asymmetries are vanishing for the case of two…
In the baryogenesis via leptogenesis scenario the self-energy contribution to the CP-violating parameter plays a very important role. Here, we calculate it in a simple toy model of leptogenesis using the Schwinger-Keldysh/Kadanoff-Baym…
In models with flavour symmetries added to the gauge group of the Standard Model the CP-violating asymmetry necessary for leptogenesis may be related with low-energy parameters. A particular case of interest is when the flavour symmetry…
We consider a type-I seesaw framework with a flavour symmetry from the series of non-abelian groups $\Delta (3 n^2)$ and $\Delta (6 n^2)$ and a CP symmetry. Breaking these symmetries non-trivially results in the right-handed neutrinos being…
Using the non-equilibrium Green function method (Kadanoff-Baym equations) in the expanding universe, we investigate evolution of the lepton number asymmetry when the right-handed (RH) neutrinos have almost degenerate masses $|M_i^2-M_j^2|…