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Related papers: Leptonic CP Violation from a New Perspective

200 papers

Some models of leptogenesis involve a nearly-degenerate pair of heavy Majorana neutrinos $N_{1,2}$ whose masses can be small, $O({\rm GeV})$. There can be heavy-light neutrino mixing parametrized by $|B_{\ell N}|^2 = 10^{-5}$, which leads…

High Energy Physics - Phenomenology · Physics 2021-04-27 David London

The seesaw extension of the SM explains the tiny neutrino masses and it is accompanied by many CP violating phases. We study the case where all leptonic CP violation arises from the soft breaking in the heavy Majorana mass matrix. Parameter…

High Energy Physics - Phenomenology · Physics 2023-11-20 C. C. Nishi , J. I. Silva-Marcos

We further study the previously proposed Ansatz, Tr(M)=0, for a prediagonal light Majorana type neutrino mass matrix. If CP violation is neglected this enables one to use the existing data on squared mass differences to estimate (up to a…

High Energy Physics - Phenomenology · Physics 2009-11-10 Salah Nasri , Joseph Schechter , Sherif Moussa

The phenomenology of 3-neutrino mixing, the current status of our knowledge about the 3-neutrino mixing parameters, including the absolute neutrino mass scale, and of the Dirac and Majorana CP violation in the lepton sector, are reviewed.…

High Energy Physics - Phenomenology · Physics 2014-05-12 S. T. Petcov

We review the current status of the data on neutrino masses and lepton mixing and the prospects for measuring the CP-violating phases in the lepton sector. The possible connection between low energy CP violation encoded in the Dirac and…

High Energy Physics - Phenomenology · Physics 2018-03-05 C. Hagedorn , R. N. Mohapatra , E. Molinaro , C. C. Nishi , S. T. Petcov

Assuming the seesaw and leptogenesis mechanisms, I give some general remarks on possible connection or disconnection between CP violation in heavy Majorana neutrino decays and that in neutrino oscillations. A simple but predictive ansatz is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Zhi-zhong Xing

One of the major open questions in the neutrino sector is the issue of leptonic CP violation. Current global oscillation data shows a mild preference for a large, potentially maximal value for the Dirac CP phase in the neutrino mixing…

High Energy Physics - Phenomenology · Physics 2016-07-20 David V. Forero , Patrick Huber

Recent experimental data provides evidence for neutrino masses and leads to the possibility of leptonic mixing and CP violation. In this work special attention is dedicated to CP violation in the leptonic sector both at low and at high…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. N. Rebelo

We hunt for and discuss manifestly CP-violating effects which are mediated by Majorana phases. These phases are present if the Standard Model neutrinos are Majorana particles. We argue that while Majorana phases do affect the strength of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Andre de Gouvea , Boris Kayser , Rabindra Mohapatra

We study effects of CP violation in a modified bipair neutrino mixing scheme predicting $\sin^2\theta_{23}$ near both 0.4 and 0.6 currently consistent with experimentally allowed values. The source of CP violation is supplied by charged…

High Energy Physics - Phenomenology · Physics 2015-06-19 Jun Iizuka , Yoshikazu Kaneko , Teruyuki Kitabayashi , Naoto Koizumi , Masaki Yasue

The current status of our knowledge of the 3-neutrino mixing parameters and of the CP violation in the lepton sector is summarised. The discrete symmetry approach to understanding the observed pattern of neutrino mixing and the related…

High Energy Physics - Phenomenology · Physics 2018-09-26 S. T. Petcov

Assuming 3-neutrino mixing and massive Majorana neutrinos, we analyze the possibility of establishing the existence of CP-violation associated with Majorana neutrinos in the lepton sector i) by measuring of the effective Majorana mass |<m>|…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Pascoli , S. T. Petcov , W. Rodejohann

In the minimal left-right symmetric model, there are only two intrinsic CP violating phases to account for all CP violation in both the quark and lepton sectors, if CP is broken spontaneously by the complex phases in the VEV's of the scalar…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mu-Chun Chen , K. T. Mahanthappa

If massive neutrinos are Majorana particles, then the lepton number should be violated in nature and neutrino-antineutrino oscillations $\nu^{}_\alpha \leftrightarrow \overline{\nu}^{}_\beta$ (for $\alpha, \beta = e, \mu, \tau$) will…

High Energy Physics - Phenomenology · Physics 2021-12-02 Yilin Wang , Shun Zhou

We review the basic mechanisms of neutrino mass generation and the corresponding structure of the lepton mixing matrix. We summarize the status of three-neutrino oscillation parameters as determined from current observations, using…

High Energy Physics - Phenomenology · Physics 2009-11-13 Hiroshi Nunokawa , Stephen Parke , Jose W. F. Valle

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

We consider a class of models of neutrino mixing with $S_4$ flavour symmetry and generalised CP symmetry, broken to $Z_2$ and $Z_2 \times {\rm CP}$ residual symmetries in the charged lepton and neutrino sectors, respectively. In this…

High Energy Physics - Phenomenology · Physics 2018-03-30 J. T. Penedo , S. T. Petcov , A. V. Titov

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 discuss a simple model of lepton mixing and CP violation based on the flavor democracy of charge leptons and the mass degeneracy of neutrinos. A nearly bi-maximal flavor mixing pattern, which is favored by current data on atmospheric and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch , Zhi-zhong Xing

We study the correlation between CP violation in neutrino oscillations and leptogenesis in the framework with two heavy Majorana neutrinos and three light neutrinos. Among three unremovable CP phases, a heavy Majorana phase contributes to…

High Energy Physics - Phenomenology · Physics 2009-11-07 T. Endoh , S. Kaneko , S. K. Kang , T. Morozumi , M. Tanimoto