English
Related papers

Related papers: On Quantum Effects in Soft Leptogenesis

200 papers

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

For standard leptogenesis from the decay of singlet right-handed neutrinos, we derive source terms for the lepton asymmetry that are present in a finite density background but absent in the vacuum. These arise from cuts through the vertex…

High Energy Physics - Phenomenology · Physics 2011-06-02 Bjorn Garbrecht

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

In thermal leptogenesis, the cosmic matter-antimatter asymmetry is produced by CP violation in the decays N --> l + \Phi of heavy right-handed Majorana neutrinos N into ordinary leptons l and Higgs particles \Phi. If some charged-lepton…

High Energy Physics - Phenomenology · Physics 2010-10-27 S. Blanchet , P. Di Bari , G. G. Raffelt

We experimentally study quantum Zeno effects in a parity-time (PT) symmetric cold atom gas periodically coupled to a reservoir. Based on the state-of-the-art control of inter-site couplings of atoms in a momentum lattice, we implement a…

Quantum Gases · Physics 2021-05-26 Tao Chen , Wei Gou , Dizhou Xie , Teng Xiao , Wei Yi , Jun Jing , Bo Yan

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

We study the effect on leptogenesis due to $B-L$ cosmic strings of a $U(1)_{B-L}$ extension of the Standard Model. The disappearance of closed loops of $B-L$ cosmic strings can produce heavy right handed neutrinos, $N_R$'s, whose…

High Energy Physics - Phenomenology · Physics 2008-11-26 Narendra Sahu , Pijushpani Bhattacharjee , Urjit A Yajnik

We study thermal leptogenesis in classes of neutrino mass models based on the seesaw mechanism with three right-handed neutrinos and sequential right-handed neutrino dominance. The flavour-dependent Boltzmann equations are solved…

High Energy Physics - Phenomenology · Physics 2009-11-11 S. Antusch , S. F. King , A. Riotto

We extend to the highly degenerate case a recent approach for analyzing the sources of CP violation in baryogenesis models with quasi-degenerate neutrinos. In this approach an expansion of the resummed propagator around the poles is plugged…

High Energy Physics - Phenomenology · Physics 2021-11-24 J. Racker

We show that when the relevant CP violating interactions in leptogenesis are fast, the different matter density asymmetries are determined at each instant by a balance condition between the amount of asymmetry being created and destroyed.…

High Energy Physics - Phenomenology · Physics 2015-05-18 Chee Sheng Fong , J. Racker

We work out the thermodynamic equations for the decays and scatterings of heavy Majorana neutrinos including the constraints from unitarity. The Boltzmann equations depend on the CP asymmetry parameter which contains both, a self-energy and…

High Energy Physics - Phenomenology · Physics 2009-10-31 Marion Flanz , Emmanuel A. Paschos

In the baryogenesis via leptogenesis scenario the self-energy contribution to the CP-violating parameter plays a very important role. Here, we calculate it in a simple toy model of leptogenesis using the Schwinger-Keldysh/Kadanoff-Baym…

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

We consider variations of the standard leptogenesis picture arising from the presence of an additional scale related to the breaking of a $U(1)_X$ abelian flavor symmetry. We show that quite generically the presence of an additional energy…

High Energy Physics - Phenomenology · Physics 2009-07-22 D. Aristizabal Sierra , Luis Alfredo Muñoz , Enrico Nardi

We point out a new effect on the freeze-out process of heavy particles induced by density perturbations in the early universe, which we call ``acoustically driven freeze-out.'' This beyond-linear effect is caused by the exponential…

High Energy Physics - Phenomenology · Physics 2025-01-20 Kenta Hotokezaka , Ryusuke Jinno , Rin Takada

We discuss some recent developments made in the computation of the baryon asymmetry generated at the electroweak scale. We emphasize that the local number density asymmetries of the particles involved in supersymmetric electroweak…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Riotto

We show that in supersymmetric models with gauged B-L symmetry, there is a new source for cosmological lepton asymmetry. The Higgs bosons responsible for B-L gauge symmetry breaking decay dominantly into right-handed sneutrinos \tilde{N}…

High Energy Physics - Phenomenology · Physics 2010-01-05 K. S. Babu , Yanzhi Meng , Zurab Tavartkiladze

We investigate how superradiance affects the generation of baryon asymmetry in a universe with rotating primordial black holes, considering a scenario where a scalar boson is coupled to the heavy right-handed neutrinos. We identify the…

High Energy Physics - Phenomenology · Physics 2024-02-20 Anish Ghoshal , Yuber F. Perez-Gonzalez , Jessica Turner

We present a new leptogenesis scenario, where the lepton asymmetry is generated by CP violating decays of heavy electroweak singlet neutrinos via electromagnetic dipole moment couplings to the ordinary light neutrinos. Akin to the usual…

High Energy Physics - Phenomenology · Physics 2008-11-26 Nicole F. Bell , Boris J. Kayser , Sandy S. C. Law

In the minimal left-right symmetric model with spontaneous CP violation, there are only two intrinsic CP violating phases to account for all CP violation in both the quark and lepton sectors. In addition, the left-and right-handed Majorana…

High Energy Physics - Phenomenology · Physics 2008-11-26 Mu-Chun Chen , K. T. Mahanthappa

An attractive explanation for non-zero neutrino masses and small matter antimatter asymmetry of the present Universe lies in "leptogenesis". At present the {\it size} of the lepton asymmetry is precisely known, while the {\it sign} is not…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kaushik Bhattacharya , Narendra Sahu , Utpal Sarkar , Santosh K. Singh