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Related papers: Leptogenesis in flavor models with type I and II s…

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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…

High Energy Physics - Phenomenology · Physics 2021-02-03 Nimmala Narendra , Narendra Sahu , S. Uma Sankar

It is shown that the mixing of lepton doublets of the Standard Model can yield sizeable contributions to the lepton asymmetry, that is generated through the decays of right-handed neutrinos at finite temperature in the early Universe. When…

High Energy Physics - Phenomenology · Physics 2015-06-11 Bjorn Garbrecht

We reveal the origin of the CP violation required by the leptogenesis in variously popular seesaw models. Especially we clarify that in a pure type-I/III seesaw with two fermion singlets/triplets, a combined type-I+III seesaw with one…

High Energy Physics - Phenomenology · Physics 2017-01-23 Pei-Hong Gu

Upper bounds on the CP asymmetry relevant for leptogenesis are reexamined and found weaker than in previous literature, both for hierarchical and for quasi-degenerate right-handed neutrinos. Successful leptogenesis implies the usual lower…

High Energy Physics - Phenomenology · Physics 2009-10-09 Thomas Hambye , Yin Lin , Alessio Notari , Michele Papucci , Alessandro Strumia

We study leptogenesis from the out-of-equilibrium decays of the lightest heavy neutrino $N_1$ in the medium (low) temperature regime, $T\lsim 10^{12}$ GeV ($10^{10}$ GeV), where the rates of processes mediated by the $\tau$ (and $\mu$)…

High Energy Physics - Phenomenology · Physics 2009-11-11 Enrico Nardi , Yosef Nir , Esteban Roulet , Juan Racker

We present a pragmatic approach to lower down the mass scale of right-handed neutrinos in leptogenesis by introducing a scalar decaying to right-handed neutrinos. The key point of our proposal is that the out-of-equilibrium decays of the…

High Energy Physics - Phenomenology · Physics 2025-07-30 Jun-Yu Tong , Zhao-Huan Yu , Hong-Hao Zhang

We show that the neutrino models, as suggested by Low, which have an additional Abelian family symmetry and a real Higgs singlet to the default see-saw do not hinder the possibility of successful thermal leptogenesis. For these models…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sandy S. C. Law , Raymond R. Volkas

We discuss gauge models incorporating $\mu-\tau$ flavored CP symmetry (called CP$^{\mu\tau}$ in the text) in combination with $L_\mu-L_\tau$ invariance to understand neutrino mixings and discuss their phenomenological implications. We show…

High Energy Physics - Phenomenology · Physics 2015-09-16 R. N. Mohapatra , C. C. Nishi

Current experimental data allow the zero value for one neutrino mass, either m_1 = 0 or m_3 = 0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m_1 = m_2 = 0 and m_3 \neq 0…

High Energy Physics - Phenomenology · Physics 2008-11-26 Aik Hui Chan , Harald Fritzsch , Shu Luo , Zhi-zhong Xing

We analyse a flavour model for a lepton sector which is based on type I seesaw mechanism, a Z_2 symmetry for lepton flavours, a mu-tau interchange symmetry and a CP symmetry. This model fits well the data of neutrino mass squared…

High Energy Physics - Phenomenology · Physics 2015-10-19 Darius Jurciukonis , Thomas Gajdosik , Andrius Juodagalvis

We introduce a novel hybrid framework combining type I and type II seesaw models for neutrino mass where a complex vacuum expectation value of a singlet scalar field breaks CP spontaneously. Using pragmatic organizing symmetries we…

High Energy Physics - Phenomenology · Physics 2023-06-21 Rohan Pramanick , Tirtha Sankar Ray , Avirup Shaw

We discuss the leptonic flavor structure generated by a brane shifted extra dimensional seesaw model with a single right handed neutrino in the bulk. In contrast to previous works, no unitarity approximation for the $3 \times 3$ submatrix…

High Energy Physics - Phenomenology · Physics 2022-10-19 Mathias Becker , Heinrich Päs

We study a type I seesaw model of neutrino masses within the framework of $A_4$ flavor symmetry. Incorporating the presence of both singlet and triplet flavons under $A_4$ symmetry, we construct the leptonic mass matrices involved in type I…

High Energy Physics - Phenomenology · Physics 2015-09-15 Rupam Kalita , Debasish Borah

We show that existing laboratory experiments have the potential to unveil the origin of matter by probing leptogenesis in the type-I seesaw model with three right-handed neutrinos and Majorana masses in the GeV range. The baryon asymmetry…

High Energy Physics - Phenomenology · Physics 2015-05-25 Laurent Canetti , Marco Drewes , Björn Garbrecht

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…

High Energy Physics - Phenomenology · Physics 2018-06-11 Matthew J. Dolan , Tomasz P. Dutka , Raymond R. Volkas

We consider tri-bimaximal lepton mixing within low-scale seesaw schemes where light neutrino masses arise from TeV scale physics, potentially accessible at the Large Hadron Collider (LHC). Two examples are considered, based on the A4 flavor…

High Energy Physics - Phenomenology · Physics 2010-05-28 M. Hirsch , S. Morisi , J. W. F. Valle

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…

High Energy Physics - Phenomenology · Physics 2009-09-11 Marta Losada , Sean Tulin

We discuss the effect of the neutrino mass scale on baryogenesis via the out-of-equilibrium decay of the lightest right-handed (s)neutrinos in type II see-saw models. We calculate the type II contributions to the decay asymmetries for…

High Energy Physics - Phenomenology · Physics 2009-11-10 Stefan Antusch , Steve F. King

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…

High Energy Physics - Phenomenology · Physics 2025-03-10 Björn Garbrecht , Edward Wang

We present a Froggatt-Nielsen flavor model that yields a minimal realization of the type-I seesaw mechanism. This seesaw model is minimal for three reasons: (i) It features only two rather than three right-handed sterile neutrinos: N_1 and…

High Energy Physics - Phenomenology · Physics 2016-12-30 Thomas Rink , Kai Schmitz , Tsutomu T. Yanagida