English
Related papers

Related papers: Spontaneous leptonic CP violation and nonzero $\th…

200 papers

We analyze the Higgs sector of the minimal $S(3)$-invariant extension of the Standard Model including CP violation arising from the spontaneous electroweak symmetry breaking. This extended Higgs sector includes three SU(2) doublets Higgs…

High Energy Physics - Phenomenology · Physics 2016-12-06 E. Barradas-Guevara , O. Félix-Beltrán , E. Rodríguez-Jáuregui

We propose that leptonic CP violation arises from a breaking of the mu-tau exchange symmetry in the neutrino mass matrix which in turn is indicated by the near maximal atmospheric neutrino mixing and the near zero \theta_{13}. We find that…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. N. Mohapatra , W. Rodejohann

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

It was commonly thought that the observation of low energy leptonic CP-violating phases would not automatically imply the existence of a baryon asymmetry in the leptogenesis scenario. This conclusion does not generically hold when the issue…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Pascoli , S. T. Petcov , A. Riotto

Viable neutrino and charged lepton masses and mixings are obtained by imposing a $S_3 \times Z_4 \times Z_3$ flavor symmetry in a model with a few additional Higgs. We use two $SU(2)_L$ triplet Higgs which are arranged as a doublet of…

High Energy Physics - Phenomenology · Physics 2008-12-30 Manimala Mitra , Sandhya Choubey

CP violation from physics beyond the Standard Model is investigated in $B_{l4}$ decays: $B\to D\pi l\bar{\nu}_l$. In the decay process, we include various excited states as intermediate states decaying to the final hadrons, $D+\pi$. We…

High Energy Physics - Phenomenology · Physics 2016-08-25 C. S. Kim , Jake Lee , W. Namgung

We find that, at the one-loop level, the spontaneous CP violation is possible in a supersymmetric standard model that has an extra chiral Higgs triplet with hypercharge Y=0. At the tree level, this triplet-extended supersymmetric standard…

High Energy Physics - Phenomenology · Physics 2008-12-09 S. W. Ham , S. K. OH

We show that in the Minimal Supersymmetric Standard Model one--loop effects at finite temperature may lead to a spontaneous breaking of CP invariance in the scalar sector. Requiring that the breaking takes place at the critical temperature…

High Energy Physics - Phenomenology · Physics 2010-11-01 D. Comelli , M. Pietroni

We consider a minimal condition that predicts the 1-3 lepton mixing angle $\theta_{13} \simeq \theta_{\rm C}/\sqrt{2}$ with $\theta_{\rm C}$ the Cabibbo angle, and give the improved prediction of $\theta_{13}$. In the case of normal mass…

High Energy Physics - Phenomenology · Physics 2016-01-19 Junpei Harada

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 propose a variant of electroweak-scale baryogenesis characterized by the spontaneous breaking of the charge-parity (CP) symmetry in the early Universe driven by the vacuum expectation value of a CP-odd scalar. This CP breaking period in…

High Energy Physics - Phenomenology · Physics 2023-05-10 S. J. Huber , K. Mimasu , J. M. No

The two principles of spontaneous CP violation and natural flavor conservation can be realized in the $SU(2)_{L}\times U(1)_{Y}$ model with two Higgs doublets. In particular, this model provides a consistent application to the CP violating…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yue-Liang Wu

The possibility of CP violation is studied in the Higgs sector of a supersymmetric standard model with multiple Higgs singlets. The tree-level Lagrangian in this model is assumed to conserve the CP symmetry. We find that CP violation is…

High Energy Physics - Phenomenology · Physics 2009-08-14 S. W. Ham , S. K. OH

Since decays to four leptons is widely considered a promising way to search for the Higgs particle, we show how the same final state can also be used to search for signals of CP nonconservation. Energy asymmetries and triple correlations…

High Energy Physics - Phenomenology · Physics 2010-11-01 A. Soni , R. M. Xu

We consider spontaneous CP violation in the Next to Minimal Supersymmetric Standard Model (NMSSM), without the usual $Z_3$ discrete symmetry. CP violation can occur at tree level, raising a potential conflict with the experimental bounds on…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. T. Davies , C. D. Froggatt , A. Usai

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

Leptogenesis via axion oscillation after inflation is an alternate mechanism of thermal leptogenesis. In this mechanism, the requirement of the existence of a lepton number ($L$) violating process in equilibrium to drive the lepton number…

High Energy Physics - Phenomenology · Physics 2025-06-17 Sasmita Mishra

In models with flavour symmetries added to the gauge group of the Standard Model the CP-violating asymmetry necessary for leptogenesis may be related with low-energy parameters. A particular case of interest is when the flavour symmetry…

High Energy Physics - Phenomenology · Physics 2009-12-04 D. Aristizabal Sierra , F. Bazzocchi , I. de Medeiros Varzielas , L. Merlo , S. Morisi

A simple Standard Model Extension based on $T_7$ flavor symmetry which accommodates lepton mass and mixing with non-zero $\theta_{13}$ and CP violation phase is proposed. At the tree- level, the realistic lepton mass and mixing pattern is…

High Energy Physics - Phenomenology · Physics 2019-05-01 V. V. Vien , H. N. Long

Taking into account the recent progress in the understanding of the lepton flavour effects in leptogenesis, we investigate in detail the possibility that the CP-violation necessary for the generation of the baryon asymmetry of the Universe…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Pascoli , S. T. Petcov , Antonio Riotto