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Related papers: Wash-In Leptogenesis

200 papers

We propose an alternative mechanism for leptogenesis at the electroweak scale, through the decays of a left-handed sneutrino. This scenario may be realized in supersymmetric models with non-zero Majorana masses for the neutrino superfield…

High Energy Physics - Phenomenology · Physics 2007-05-23 John Ellis , Sin Kyu Kang

We have studied the scenario of baryogenesis via leptogenesis in an $A_4$ flavor symmetric framework considering type I seesaw as the origin of neutrino mass. Because of the presence of the fifth generation right handed neutrino the model…

High Energy Physics - Phenomenology · Physics 2018-03-23 Ananya Mukherjee , Mrinal Kumar Das , Jayanta Kumar Sarma

Polynomial inflation is a very simple and well motivated scenario. A potential with a concave ``almost'' saddle point at field value $\phi = \phi_0$ fits well the cosmic microwave background (CMB) data and makes testable predictions for the…

High Energy Physics - Phenomenology · Physics 2024-02-28 Manuel Drees , Yong Xu

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…

High Energy Physics - Phenomenology · Physics 2025-07-21 Alessandro Granelli , Koichi Hamaguchi , Maura E. Ramirez-Quezada , Kengo Shimada , Juntaro Wada , Tatsuya Yokoyama

If the baryon asymmetry of the Universe is produced by leptogenesis, CP violation is required in the lepton sector. In the seesaw extension of the Standard Model with three hierarchical right-handed neutrinos, we show that the baryon…

High Energy Physics - Phenomenology · Physics 2008-11-26 Sacha Davidson , Julia Garayoa , Federica Palorini , Nuria Rius

We present a novel realization of leptogenesis from the decays of sterile (right-handed) neutrinos (RHNs) produced from runaway bubble collisions at a first order phase transition. Such configurations can produce heavy RHNs with mass many…

High Energy Physics - Phenomenology · Physics 2024-12-05 Martina Cataldi , Bibhushan Shakya

We consider leptogenesis in scenarios with many neutrino singlets. We find that the lower bound for the reheating temperature can be significantly relaxed with respect to the hierarchical three neutrino case. We further argue that the upper…

High Energy Physics - Phenomenology · Physics 2008-11-26 Marc-Thomas Eisele

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass…

High Energy Physics - Phenomenology · Physics 2015-06-18 Pasquale Di Bari , Sophie E. King , Michele Re Fiorentin

We study the supersymmetric leptogenesis via $LH_{u}$ flat direction with a gauged $U(1)_{B-L}$ symmetry. We find that the resultant baryon asymmetry is enhanced compared with the case without a gauged $U(1)_{B-L}$ symmetry. The baryon…

High Energy Physics - Phenomenology · Physics 2009-11-07 Masaaki Fujii , K. Hamaguchi , T. Yanagida

In the type-I seesaw mechanism for neutrino masses, there exists a $B-L$ symmetry, whose breaking leads to the lepton number violating mass of the heavy Majorana neutrinos. This would imply the existence of a new neutral scalar associated…

High Energy Physics - Phenomenology · Physics 2018-02-16 P. S. Bhupal Dev , Rabindra N. Mohapatra , Yongchao Zhang

Measuring a non-zero value for the cross section of any lepton number violating (LNV) process would put a strong lower limit on the washout factor for the effective lepton number density in the early universe at times close to the…

High Energy Physics - Phenomenology · Physics 2014-06-24 Frank F. Deppisch , Julia Harz , Martin Hirsch

A one-flavour naturalness argument suggests that the Type I seesaw model cannot naturally explain neutrino masses and the baryon asymmetry of the Universe via hierarchical thermal leptogenesis. We prove that there is no way to avoid this…

High Energy Physics - Phenomenology · Physics 2015-09-25 Jackson D. Clarke

We present here a novel and testable mechanism for leptogenesis, which is characterized by a purely thermal generation of lepton asymmetry via scalar decay. Guided by the thermal mass matrix diagonalization in the finite-temperature regime,…

High Energy Physics - Phenomenology · Physics 2022-01-05 Shao-Ping Li , Xin-Qiang Li , Xin-Shuai Yan , Ya-Dong Yang

In the framework of type II seesaw mechanism we propose two simple but instructive ansatze for neutrino mixing and leptogenesis. In each ansatz, the effective Majorana neutrino mass matrix is composed of two parts -- the part with Z_2…

High Energy Physics - Phenomenology · Physics 2008-11-26 Wan-lei Guo

We show that the leptogenesis is automatic within the supersymmetric standard model if there exist right-handed neutrinos with mass less than $H_{\it inf}$, the expansion rate during the inflation. Its scalar component grows during the…

High Energy Physics - Phenomenology · Physics 2009-09-29 Hitoshi Murayama , T. Yanagida

We investigate how the baryon asymmetry of our universe via leptogenesis can be achieved within the framework of the seesaw model with Fritzsch type lepton mass matrices proposed by Fukugita $et. al$. We study the cases with CP-violating…

High Energy Physics - Phenomenology · Physics 2008-11-26 Y. H. Ahn , Sin Kyu Kang , C. S. Kim , Jake Lee

If an exact $\mu\leftrightarrow \tau$ symmetry is the explanation of the maximal atmospheric neutrino mixing angle, it has interesting implications for origin of matter via leptogenesis in models where small neutrino masses arise via the…

High Energy Physics - Phenomenology · Physics 2009-11-10 R. N. Mohapatra , S. Nasri

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…

High Energy Physics - Phenomenology · Physics 2017-09-13 Marco Drewes , Bjorn Garbrecht , Dario Gueter , Juraj Klaric

The right-handed neutrinos within the type-I seesaw mechanism can induce large radiative corrections to the Higgs mass, and naturalness arguments can then be used to set limits on their mass scale and Yukawa couplings. Driven by minimality,…

High Energy Physics - Phenomenology · Physics 2017-05-23 Gulab Bambhaniya , P. S. Bhupal Dev , Srubabati Goswami , Subrata Khan , Werner Rodejohann

In the Type I see-saw model, the naturalness requirement that corrections to the electroweak $\mu$ parameter not exceed 1 TeV results in a rough bound on the lightest right-handed neutrino mass, $M_{N_1}\lesssim 3\times 10^7$ GeV. In this…

High Energy Physics - Phenomenology · Physics 2015-04-16 Jackson D. Clarke , Robert Foot , Raymond R. Volkas