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Related papers: Lepton asymmetry and the cosmic QCD transition

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In this talk, we first make some brief comments on the phase-convention dependence of the CP-violating parameter \epsilon_B. A simple framework is then presented for analyzing new physics contributions to B^0-\bar{B}^0 mixing and their…

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

In leptogenesis scenario, the decays of heavy Majorana neutrinos generate lepton family asymmetries, $Y_e, Y_{\mu}$ and $Y_{\tau}$. They are sensitive to CP violating phases in seesaw models. The time evolution of the lepton family…

High Energy Physics - Phenomenology · Physics 2009-11-10 T. Endoh , T. Morozumi , Z. Xiong

We propose a novel scenario to explain the observed cosmological asymmetry between matter and antimatter, based on nonperturbative QCD physics. This scenario relies on a mechanism of separation of quarks and antiquarks in two coexisting…

High Energy Physics - Phenomenology · Physics 2009-11-10 David H. Oaknin , Ariel Zhitnitsky

We consider a minimal supersymmetric extension of the Standard Model, with right-handed neutrinos and local B-L, the difference between baryon and lepton number, a symmetry which is spontaneously broken at the scale of grand unification. To…

High Energy Physics - Phenomenology · Physics 2015-04-09 Wilfried Buchmüller , Valerie Domcke , Kohei Kamada , Kai Schmitz

Primordial Big-Bang Nucleosynthesis (BBN) tightly constrains the existence of any additional relativistic degrees of freedom at that epoch. However a large asymmetry in electron neutrino number shifts the chemical equilibrium between the…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. March-Russell , H. Murayama , A. Riotto

The cosmological baryon asymmetry is closely related to neutrino properties due to the non-perturbative sphaleron processes in the high-temperature symmetric phase of the standard model. We review some aspects of this connection with…

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

We discuss the possibility of relating the size and sign of the observed baryon asymmetry of the universe to CP violation observable at low energies, in a framework where the observed baryon asymmetry is produced by leptogenesis through out…

High Energy Physics - Phenomenology · Physics 2007-05-23 G. C. Branco , T. Morozumi , B. M. Nobre , M. N. Rebelo

The presence of flavor symmetries in the lepton sector may have several consequences for the generation of the baryon asymmetry of the Universe via leptogenesis. We review the mechanism in general type-I, type-II and type-III seesaw models.…

High Energy Physics - Phenomenology · Physics 2015-06-05 D. Aristizabal Sierra , I. de Medeiros Varzielas

We propose a resonant leptogenesis scenario in a U(1)_{B-L} gauge extension of the standard model to generate large lepton asymmetries for cosmological baryon asymmetry and dark matter. After B-L number is spontaneously broken, inflaton can…

High Energy Physics - Phenomenology · Physics 2010-12-09 Pei-Hong Gu

We propose a new mechanism of baryogenesis which proceeds via a CP-violating phase transition. During this phase transition, the coupling of the Weinberg operator is dynamically realised and subsequently a lepton asymmetry is generated via…

High Energy Physics - Phenomenology · Physics 2017-04-28 Silvia Pascoli , Jessica Turner , Ye-Ling Zhou

It is shown that the mixing of lepton doublets of the Standard Model can yield sizeable contributions to the lepton asymmetry, that is generated through the decays of right-handed neutrinos at finite temperature in the early Universe. When…

High Energy Physics - Phenomenology · Physics 2015-06-11 Bjorn Garbrecht

We investigate the generation of the baryon asymmetry of the Universe within a SUSY SU(5) x T' model of flavour, which gives rise to realistic masses and mixing patterns for quarks and leptons. The model employs the see-saw mechanism for…

High Energy Physics - Phenomenology · Physics 2012-03-21 A. Meroni , E. Molinaro , S. T. Petcov

The origin of the matter-antimatter asymmetry of the universe is one of the major unsolved problems in cosmology and particle physics. In this paper, we investigate the recently proposed possibility that split fermion models -- extra…

High Energy Physics - Phenomenology · Physics 2009-11-11 Andrew Coulthurst

We calculate the baryonic asymmetry of the universe in the baryogenesis-via-leptogenesis framework, assuming first a quark-lepton symmetry and then a charged-neutral lepton symmetry. We match the results with the experimentally favoured…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Falcone , F. Tramontano

Several models of baryo(lepto)-genesis that give rise to large inhomogeneities in the composition of the universe are presented. In particular, a variation of primordial abundances of light elements by the factor 2-5 at large distances is…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. D. Dolgov

Fermions scattering off first-order phase transition bubbles, in the framework of $SU(2)_L\otimes SU(2)_R\otimes U(1)$ models, may generate the Baryon Asymmetry of the Universe (BAU), either at the $LR$-symmetry-breaking scale, or at the…

High Energy Physics - Phenomenology · Physics 2010-11-01 J. -M. Frère , L. Houart , J. M. Moreno , J. Orloff , M. Tytgat

We examine the generation of baryon asymmetry at the weak scale from a primordial lepton asymmetry. If the electroweak phase transition is first order, partial reflection of tau leptons off the bubble walls and the resulting hypercharge…

High Energy Physics - Phenomenology · Physics 2009-10-28 S. A. Abel , K. E. C. Benson

It is well known that when a fermion propagates in curved space-time, its spin couples to the curvature of background space-time. We propose that this interaction for neutrinos propagating in early curved universe could give rise to a new…

High Energy Physics - Phenomenology · Physics 2009-11-11 Ujjal Debnath , Banibrata Mukhopadhyay , Naresh Dadhich

We relate leptogenesis in a class of theories to low-energy experimental observables: quark and lepton masses and mixings. With reasonable assumptions motivated by grand unification, one can show that the CP-asymmetry parameter takes a…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. S. Berger , Kim Siyeon

Neutrinoless double beta decay, lepton number violating collider processes and the Baryon Asymmetry of the Universe (BAU) are intimately related. In particular lepton number violating processes at low energies in combination with sphaleron…

High Energy Physics - Phenomenology · Physics 2015-05-29 Julia Harz , Wei-Chih Huang , Heinrich Päs