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Related papers: Leptogenesis without CP Violation at Low Energies

200 papers

We investigate a scheme for making leptogenesis by means of the CP violating decays of the seesaw Majorana neutrinos proposed by Fukugita and Yanagida. However, in order to avoid the wash-out of the produced lepton number we propose the…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Asaka , H. B. Nielsen , Y. Takanishi

The high scale mixing unification hypothesis recently proposed by three of us (R. N. M., M. K. P. and G. R.) states that if at the seesaw scale, the quark and lepton mixing matrices are equal then for quasi-degenerate neutrinos, radiative…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. K. Agarwalla , M. K. Parida , R. N. Mohapatra , G. Rajasekaran

We have studied mixing and masses of three left handed Majorana neutrinos in the model, which assumes exactly degenerate neutrino masses at some "neutrino unification" scale. Such a simple theoretical ansatz naturally leads to…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. N. Ioannisian , N. A. Kazarian

The necessary complex structures needed for CP violation are not easy to generate and, indeed, CP can be a symmetry in higher dimensional theories. In 4-dimensions CP violation argues for the existence of a scalar sector and, in its…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. D. Peccei

We demonstrate the ability to measure the CP-phase of a Higgs boson state by looking at the decays of heavy, Majorana neutrinos in the process $pp \to H \to N N$ at the LHC. This is shown for signals with both opposite-sign ($l^{\pm}…

High Energy Physics - Phenomenology · Physics 2011-08-04 Vernon Barger , Wai-Yee Keung , Brian Yencho

In the canonical seesaw mechanism, the strengths of charged-current interactions for light and heavy Majorana neutrinos are described respectively by the $3\times 3$ matrices $U$ and $R$ that are correlated with each other via the exact…

High Energy Physics - Phenomenology · Physics 2025-08-05 Zhi-zhong Xing

We investigate under which circumstances one can show the existence of leptonic CP violation with the help of a positive or negative signal in neutrinoless double beta decay. The possibilities of cancellations are investigated for special…

High Energy Physics - Phenomenology · Physics 2007-05-23 W. Rodejohann

Discovery of the CP-violation in the lepton sector is one of the challenges of the particle physics. We search for possible principles, symmetries and phenomenological relations that can lead to particular values of the CP-violating Dirac…

High Energy Physics - Phenomenology · Physics 2010-10-27 Y. Farzan , A. Yu. Smirnov

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.…

High Energy Physics - Phenomenology · Physics 2016-11-28 Marco Drewes , Bjorn Garbrecht , Dario Gueter , Juraj Klaric

We consider left-right symmetric model with spontaneous CP-violation. The Lagrangian of this model is CP invariant and the Yukawa couplings are real. Due to spontaneous breaking of the gauge symmetry, some of the neutral Higgses acquire…

High Energy Physics - Phenomenology · Physics 2014-11-18 Narendra Sahu , S. Uma Sankar

We study the conditions under which the Majorana phase of the two flavor neutrino mixing matrix appears in the oscillation probabilities and causes $CP$ violation. We find that the Majorana phase remains in the neutrino evolution equation…

High Energy Physics - Phenomenology · Physics 2023-01-11 Khushboo Dixit , Akhila Kumar Pradhan , S. Uma Sankar

The phenomenology of the most general lepton mass matrices obtained through weak basis transformations has been discussed. Using a hierarchical parametrization of these mass matrices, the exact relations for lepton mixing angles have been…

High Energy Physics - Phenomenology · Physics 2013-12-06 Rohit Verma

The Daya Bay Collaboration (An et al) has recently proclaimed discovery of non-zero reactor angle, $\theta_{13}$, $\sin^{2}2\theta_{13}$=0.092$\pm$0.016(stat)$\pm$0.005(syst), at $5.2\sigma$ which is in conformity with the earlier…

High Energy Physics - Phenomenology · Physics 2012-07-17 Surender Verma

We propose a simple model for the spontaneous CP violation based on $SU(2)_{L}\times U(1)_{Y}\times A_{4}\times CP\times Z_{2}$ symmetry for quarks and leptons in a seesaw framework. In our model CP is spontaneously broken at high energies,…

High Energy Physics - Phenomenology · Physics 2013-09-03 Y. H. Ahn , Seungwon Baek

In the present work we study both thermal and non-thermal leptogenesis in all neutrino mass models describing the presently available neutrino mass patterns. We consider the Majorana CP violating phases coming from right-handed Majorana…

High Energy Physics - Phenomenology · Physics 2008-07-16 N. Nimai Singh , H. Zeen Devi , Amal Kr Sarma

We investigate effects of non-zero Dirac and Majorana CP violating phases on neutrino-antineutrino oscillations in a magnetic field of astrophysical environments. It is shown that in the presence of strong magnetic fields and dense matter,…

High Energy Physics - Phenomenology · Physics 2021-06-30 Artem Popov , Alexander Studenikin

We explore the theoretical constraints on the observable parameters of neutrino mixing on predictions for the leptonic Dirac CP-violating phase within a well-studied class of simple theoretical models that includes a single source of CP…

High Energy Physics - Phenomenology · Physics 2022-10-06 Lisa L. Everett , Raymundo Ramos , Ariel B. Rock , Alexander J. Stuart

Baryogenesis via leptogenesis is investigated in a specific model of light neutrino masses and mixing angles. The latter was proposed on the basis of an assumed complex-extended scaling property of the neutrino Majorana mass matrix $M_\nu$,…

High Energy Physics - Phenomenology · Physics 2017-03-22 Rome Samanta , Mainak Chakraborty , Probir Roy , Ambar Ghosal

We examine the constraints on the MNS lepton mixing matrix from the present and future experimental data of the neutrino oscillation and lepton number violation processes. We introduce a graphical representation of the CP violation phases…

High Energy Physics - Phenomenology · Physics 2014-11-17 K. Matsuda , N. Takeda , T. Fukuyama , H. Nishiura

We discuss leptogenesis in a model with heavy right-handed Majorana neutrinos propagating in a constant but otherwise generic CPT-violating axial time-like background (which could be motivated by string theory considerations). At…

High Energy Physics - Phenomenology · Physics 2018-04-04 Thomas Bossingham , Nick E. Mavromatos , Sarben Sarkar