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} and \tilde{N}* producing an asymmetry in \tilde{N} over \tilde{N}*. This can be fully converted into ordinary lepton asymmetry in the decays of \tilde{N}. In simple models with gauged B-L symmetry we show that resonant/soft leptogenesis is naturally realized. Supersymmetry guarantees quasi-degenerate scalar states, while soft breaking of SUSY provides the needed CP violation. Acceptable values of baryon asymmetry are obtained without causing serious problems with gravitino abundance.
Leptogenesis and Dark Matter in an Inverse Seesaw from gauged B-L breaking
Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid(马德里自治大学理论物理研究所);Departamento de Física Matemática, Instituto de Física Universidade de São Paulo(圣保罗大学物理学院数学物理系);Dipartimento di Fisica e Astronomia, Università di Bologna(博洛尼亚大学物理与天文学系);INFN, Sezione di Bologna(意大利国家核物理研究所博洛尼部分所);Institute for Astroparticle Physics (IAP), Karlsruhe Institute of Technology (KIT)(卡尔斯鲁厄理工学院亚原子物理研究所);Niels Bohr Institute, University of Copenhagen(哥本哈根大学尼尔斯玻尔研究所)
We perform a thermal unflavored leptogenesis analysis on minimal left-right symmetric models with discrete left-right symmetry identified as generalized parity or charge conjugation. When left-right symmetry is unbroken in the lepton Yukawa sector, the neutrino Dirac coupling matrix is completely determined by neutrino masses and mixing angles, allowing CP violation needed to generate leptogenesis totally resides in the low-energy sector. With two lepton asymmetry generation ways, both type I and mixed type I$+$II neutrino mass generation mechanisms are considered. After solving the Boltzmann …
Extensions of the Standard Model (SM) with sterile neutrinos are well motivated from the observed oscillations of the light neutrinos and they have shown to successfully explain the Baryon Asymmetry of the Universe (BAU) through, for instance, the so-called ARS leptogenesis. Sterile neutrinos can be added in minimal ways to the SM, but many theories exist where sterile neutrinos are not the only new fields. Such theories often include scalar bosons, which brings about the possibility of further interactions between the sterile neutrinos and the SM. In this paper we consider an extension of the…
Motivated by the growing evidence for the possible lepton flavour universality violation after the first results from Fermilab's muon $(g-2)$ measurement, we revisit one of the most widely studied anomaly free extensions of the standard model namely, gauged $L_μ-L_τ$ model, to find a common explanation for muon $(g-2)$ as well as baryon asymmetry of the universe via leptogenesis. The minimal setup allows TeV scale resonant leptogenesis satisfying light neutrino data while the existence of light $L_μ-L_τ$ gauge boson affects the scale of leptogenesis as the right handed neutrinos are charged un…
We use $S_4$ discrete group to construct a neutrino flavour model which leads to $TM_1$ mixing and is consistent with the neutrino oscillation data. Using the model's constrained parameter space, we predict the values of Dirac $CP$ phase and the light neutrino mass as $-1<\sin δ<-0.9$ and $1.7<m_1 (\text{meV})<5.5$ respectively. We thoroughly examine the usefulness of this model in explaining the observed baryon asymmetry of the Universe. Near-maximal breaking of CP symmetry (arising due to the $\text{TM}_1$ constraint) helps us in generating adequate baryon asymmetry through leptogenesis. We …
Non-Thermal Leptogenesis in the BLSM with Inverse Seesaw Mechanism
Division de Ciencias e Ingenierías, Universidad de Guanajuato(瓜纳华托大学科学与工程分院);Centre for Theoretical Physics, Zewail City of Science and Technology(泽维尔科学与技术城理论物理中心)
We study the possibility of realising cosmic inflation, dark matter (DM), baryon asymmetry of the universe (BAU) and light neutrino masses in non-supersymmetric minimal gauged $B-L$ extension of the standard model with three right handed neutrinos. The singlet scalar field responsible for spontaneous breaking of $B-L$ gauge symmetry also plays the role of inflaton by virtue of its non-minimal coupling to gravity. While the lightest right handed neutrino is the DM candidate, being stabilised by an additional $Z_2$ symmetry, we show by performing a detailed renormalisation group evolution (RGE) …
KTH Royal Institute of Technology(皇家理工学院);Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid(马德里自治大学理论物理研究所);Universidad Complutense de Madrid(马德里康普顿斯大学);Universidad de Castilla-La Mancha(卡斯蒂利亚-拉曼恰大学)
In order to address the baryon asymmetry in the Universe one needs to understand the origin of baryon (B) and lepton (L) number violation. In this article, we discuss the mechanism of baryogenesis via leptogenesis to explain the matter-antimatter asymmetry in theories with spontaneous breaking of baryon and lepton number. In this context, a lepton asymmetry is generated through the out-of-equilibrium decays of right-handed neutrinos at the high-scale, while local baryon number must be broken below the multi-TeV scale to satisfy the cosmological bounds on the dark matter relic density. We demon…
Oklahoma State University(俄克拉荷马州立大学);Universitat de València(瓦伦西亚大学);Physical Research Laboratory(物理研究实验室);Carleton University(卡尔顿大学);Queen's University(女王大学)