English
Related papers

Related papers: CP Violation in Seesaw Model

200 papers

We propose a simplified version of the inverse seesaw model, in which only two pairs of the gauge-singlet neutrinos are introduced, to interpret the observed neutrino mass hierarchy and lepton flavor mixing at or below the TeV scale. This…

High Energy Physics - Phenomenology · Physics 2009-09-28 Michal Malinsky , Tommy Ohlsson , Zhi-zhong Xing , He Zhang

For flavor neutrino masses M^{PDG}_{ij} (i,j=e,mu,tau) compatible with the phase convention defined by Particle Data Group (PDG), if neutrino mixings are controlled by small corrections to those with sin(theta_{13})=0 denoted by…

High Energy Physics - Phenomenology · Physics 2015-06-05 Masaki Yasue

We discuss the Dirac CP violating phase $\delta_{CP}$ in the Froggatt-Nielsen model for a neutrino mass matrix $M_\nu$ imposing a condition ${\rm det} [M_\nu]=0$. This additional condition restricts the CP violating phase $\delta_{CP}$…

High Energy Physics - Phenomenology · Physics 2017-05-17 Yuya Kaneta , Morimitsu Tanimoto , Tsutomu T. Yanagida

Enlightened by the idea of the 3 times 3 CKM angle matrix proposed recently by Harrison et al., we introduce the Dirac angle matrix Phi and the Majorana angle matrix Psi in the lepton sector for Dirac and Majorana neutrinos respectively. We…

High Energy Physics - Phenomenology · Physics 2015-05-30 Shu Luo

We propose a democratic-type neutrino mass matrix based on $Z_3$ symmetry. This mass matrix predicts the CP violation phase, $\delta=\pi/2$, and the mixing angle between the mass eigenstates $\nu_2$ and $\nu_3$, $\sin^2 \theta_{23}= \cos^2…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kiko Fukuura , Takahiro Miura , Eiichi Takasugi , Masaki Yoshimura

We consider a supersymmetric SU(4)$_c \times$SU(2)$_L \times$SU(2)$_R$ model with a minimal number of Higgs multiplets and Dirac and Majorana $CP$-violating phases in the neutrino flavor mixing matrix. The model incorporates the charged…

High Energy Physics - Phenomenology · Physics 2018-09-12 Nobuchika Okada , Qaisar Shafi

We investigate the see-saw mechanism for generally non-fine-tuned $n \times n$ mass matrices involving both Dirac and Majorana neutrinos. We specifically show that the number of naturally light neutrinos cannot exceed half of the dimension…

High Energy Physics - Phenomenology · Physics 2009-11-07 Manfred Lindner , Tommy Ohlsson , Gerhart Seidl

In the framework of the seesaw mechanism, and adopting a typical form for the Dirac neutrino mass matrix, we discuss the impact of minimal forms of the Majorana neutrino mass matrix. These matrices contain four or three texture zeros and…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Falcone

We explore the prospects for observing CP violation in the minimal supersymmetric extension of the Standard Model (MSSM) with six CP-violating parameters, three gaugino mass phases and three phases in trilinear soft supersymmetry-breaking…

High Energy Physics - Phenomenology · Physics 2015-03-03 A. Arbey , J. Ellis , R. M. Godbole , F. Mahmoudi

CP violation in $B$ decays is reviewed in the Standard Model (SM) and beyond the SM. The present explanation of CP violation in terms of a phase in the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be tested through a variety of CP asymmetries…

High Energy Physics - Phenomenology · Physics 2016-09-06 Michael Gronau

We discuss the energy scale profile of the bi-maximal mixing which is given at the GUT energy scale in the minimal SUSY model, associated with an assumption that Y_nu^dagger Y_nu is diagonal, where Y_nu is the neutrino-Yukawa coupling…

High Energy Physics - Phenomenology · Physics 2009-11-10 Tetsuo Shindou , Eiichi Takasugi

We study mixing and CP violation of three left-handed Majorana neutrinos in the limit of exactly degenerate masses, identify the weak-basis invariant relevant for CP violation and show that the leptonic mixing matrix is parametrized only by…

High Energy Physics - Phenomenology · Physics 2009-10-31 G. C. Branco , M. N. Rebelo , J. I. Silva-Marcos

We analyse the interplay of generalised CP transformations and the non-Abelian discrete group $T^{\prime}$ and use the semi-direct product $G_f= T^{\prime}\rtimes H_{\text{CP}}$, as family symmetry acting in the lepton sector. The family…

High Energy Physics - Phenomenology · Physics 2014-05-20 Ivan Girardi , Aurora Meroni , S. T. Petcov , Martin Spinrath

We explore possible CP violating effects, coming from the Dirac phase of the Maki-Nakagawa-Sakata-Pontecorvo matrix, on the neutrino degeneracy parameters, at the epoch of Big-Bang nucleosynthesis. We first demonstrate the conditions under…

High Energy Physics - Phenomenology · Physics 2014-11-20 J. Gava , C. Volpe

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that…

High Energy Physics - Phenomenology · Physics 2017-08-23 Paul H. Frampton

We count the number of CP breaking phases in models with $SU(2)_L\times U(1)_Y$ and $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ electroweak gauge groups and extended matter contents with some fermion masses vanishing and/or degenerate. Quarks…

High Energy Physics - Phenomenology · Physics 2007-05-23 F. del Aguila , M. Zralek

Assuming mixing of three massive Majorana neutrinos, we study the implications of the neutrino oscillation solutions of the solar and atmospheric neutrino problems and of the results of the CHOOZ experiment for the predictions of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. M. Bilenky , S. Pascoli , S. T. Petcov

We highlight in a model independent way the dependence of the effective Majorana mass parameter, relevant for neutrinoless double beta decay, on the CP phases of the PMNS matrix, using the most recent neutrino data including the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Asmaa Abada , Gautam Bhattacharyya

We study decoherence effects on mixing among three generations of neutrinos. We show that in presence of a non--diagonal dissipation matrix, both Dirac and Majorana neutrinos can violate the $CPT$ symmetry and the oscillation formulae…

High Energy Physics - Phenomenology · Physics 2020-12-02 Luca Buoninfante , Antonio Capolupo , Salvatore M. Giampaolo , Gaetano Lambiase

If massive neutrinos are Majorana particles, then the lepton number should be violated and neutrino-antineutrino oscillations will take place. In this talk, we present the properties of CP violation in neutrino-antineutrino oscillations…

High Energy Physics - Phenomenology · Physics 2022-09-12 Yilin Wang , Shun Zhou