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Related papers: Revisiting the Minimal Nelson-Barr Model

200 papers

The origin of neutrino masses can be simply attributed to a new scalar beyond the Standard Model. We demonstrate that leptogenesis can explain the baryon asymmetry of the universe already in such a minimal framework, where the electroweak…

High Energy Physics - Phenomenology · Physics 2025-08-06 Shinya Kanemura , Shao-Ping Li

Left-Right symmetric theories solve the strong CP problem and explain the small Higgs quartic coupling at high energy scales via the Higgs Parity mechanism, which forces the Higgs quartic coupling to vanish at the Left-Right symmetry…

High Energy Physics - Phenomenology · Physics 2021-05-19 David Dunsky , Lawrence J. Hall , Keisuke Harigaya

We present a model of leptogenesis that preserves lepton number. The model maintains the important feature of more traditional leptogenesis scenarios: the decaying particles that provide the CP violation necessary for baryogenesis also…

High Energy Physics - Phenomenology · Physics 2009-09-29 Hitoshi Murayama , Aaron Pierce

Violated mirror symmetry (MS) is capable of reproducing observed qualitative properties of weak mixing for quarks and leptons. In violated MS, lepton phenomenology, that is, small neutrino masses and mixing properties different from those…

High Energy Physics - Phenomenology · Physics 2017-05-24 Igor T. Dyatlov

We propose simple scoto-seesaw models to account for dark matter and neutrino masses with spontaneous CP violation. This is achieved with a single horizontal $\mathcal{Z}_8$ discrete symmetry, broken to a residual $\mathcal{Z}_2$ subgroup…

High Energy Physics - Phenomenology · Physics 2021-05-12 D. M. Barreiros , F. R. Joaquim , R. Srivastava , J. W. F. Valle

Recent years have seen a great improvement in the computation of $CP$-conserving and $CP$-violating equilibration rates for leptogenesis. These are relevant for the relativistic regime of the sterile Majorana fermions and the dynamics of…

High Energy Physics - Phenomenology · Physics 2025-03-10 Björn Garbrecht , Edward Wang

In two recent papers, arXiv:0909.1559 and arXiv:0911.4122, it has been demonstrated that one can obtain quantum corrected Boltzmann kinetic equations for leptogenesis using a top-down approach based on the Schwinger-Keldysh/Kadanoff-Baym…

High Energy Physics - Phenomenology · Physics 2010-05-12 M. Garny , A. Hohenegger , A. Kartavtsev

In the standard model QCD Lagrangian, a term of CP violating gluon density is theoretically expected to have a physical coefficient $\bar{\theta}$ of the order of unity. However, the upper bound on the electric dipole moment of neutron…

High Energy Physics - Phenomenology · Physics 2023-07-12 Pei-Hong Gu

We consider the minimal supersymmetric triplet seesaw model as the origin of neutrino masses and mixing as well as of the baryon asymmetry of the Universe, which is generated through soft leptogenesis employing a CP violating phase and a…

High Energy Physics - Phenomenology · Physics 2009-11-11 E. J. Chun , S. Scopel

The majoron is the Nambu-Goldstone boson associated with the spontaneous breaking of a global $B-L$ symmetry. Remarkably, the minimal majoron framework can simultaneously address three key empirical indications of physics beyond the…

High Energy Physics - Phenomenology · Physics 2026-05-20 Arturo de Giorgi , Daniel Naredo-Tuero , Xavier Ponce Díaz

We discuss the connection between observable CP violation in the lepton sector, the properties of heavy neutrinos and the baryon asymmetry of the universe in the minimal seesaw model. A measurement of the Dirac phase $\delta$ would allow to…

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

We study thermal leptogenesis induced by decays of a scalar SU(2)_L triplet. Despite the presence of gauge interactions, unexpected features of the Boltzmann equations make the efficiency close to maximal in most of the parameter space. We…

High Energy Physics - Phenomenology · Physics 2009-10-09 Thomas Hambye , Martti Raidal , Alessandro Strumia

We point out that the long-standing strong CP problem may be resolved by an anthropic argument. The key ideas are: (i) to allow explicit breaking(s) of the Peccei-Quinn symmetry which reduces the strong CP problem to the cosmological…

High Energy Physics - Phenomenology · Physics 2009-05-30 Fuminobu Takahashi

It is shown that the minimal Left-Right symmetric model admits cosmic string, domain wall and conditionally, monopole solutions. The strings arise when the $SU(2)_R$ is broken and can either be destabilized at the electroweak scale or…

High Energy Physics - Phenomenology · Physics 2007-05-23 U. A. Yajnik , Hatem Widyan , Shobhit Mahajan , Amitabha Mukherjee , Debajyoti Choudhari

We investigate the scenario of resonant thermal leptogenesis, in which the leptonic asymmetries are generated through renormalization group corrections induced at the leptogenesis scale. In the framework of the standard model extended by…

High Energy Physics - Phenomenology · Physics 2009-11-11 G. C. Branco , R. Gonzalez Felipe , F. R. Joaquim , B. M. Nobre

Three possible strategies have been advocated to solve the strong CP problem. The first is the axion, a dynamical mechanism that relaxes any initial value of the CP violating angle $\bar{\theta}$ to zero. The second is the imposition of new…

High Energy Physics - Phenomenology · Physics 2025-05-14 David E. Kaplan , Tom Melia , Surjeet Rajendran

To explain the baryon asymmetry in the early universe via leptogenesis, quantum corrections to new particles are commonly invoked to generate the necessary CP asymmetry. We demonstrate, however, that a large CP asymmetry can already arise…

High Energy Physics - Phenomenology · Physics 2025-05-27 Shinya Kanemura , Shao-Ping Li

We investigate how the solution to the strong CP problem and the explanation for the observed fermion mass hierarchies can be intrinsically related. Specifically, we explore the Nelson-Barr mechanism and identify its "seesaw limit", where…

High Energy Physics - Phenomenology · Physics 2024-12-25 A. L. Cherchiglia , A. G. Dias , J. Leite , C. C. Nishi

Recent developments in thermal leptogenesis are reviewed. Neutrino mixing data favor a simple picture where the matter-anti matter asymmetry is generated by the decays of the heavy RH neutrinos mildly close to thermal equilibrium and,…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Di Bari

One often hears that the strong $CP$ problem is the one problem which cannot be solved by anthropic reasoning. We argue that this is not so. Due to nonperturbative dynamics, states with a different $CP$ violating paramenter $\theta$ acquire…

High Energy Physics - Theory · Physics 2017-12-11 Nemanja Kaloper , John Terning