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Related papers: Instant nonthermal leptogenesis

200 papers

The gravitino problem gives a severe constraint on the thermal leptogenesis scenario. This problem leads us to consider some alternatives to it if we try to keep the gravitino mass around the weak scale $m_{3/2} \sim 100$ GeV. We consider,…

High Energy Physics - Phenomenology · Physics 2009-11-11 Takeshi Fukuyama , Tatsuru Kikuchi , Toshiyuki Osaka

We revisit the nonthermal gravitino production at the (p)reheating stage after inflation. Particular attention is paid to large field inflation models with a $\mathbb{Z}_2$ symmetry, for which the previous perturbative analysis is…

High Energy Physics - Phenomenology · Physics 2016-12-06 Yohei Ema , Kyohei Mukaida , Kazunori Nakayama , Takahiro Terada

We investigate a non-instantaneous reheating period in the early Universe, where the inflaton field decays exclusively to right-handed neutrinos (RHNs). The subsequent decay of these RHNs into Standard Model particles not only drives the…

High Energy Physics - Phenomenology · Physics 2026-01-01 Arghyajit Datta , Shaaban Khalil , Rajat Kumar Mandal , Arunansu Sil

We consider a model of baryogenesis based on adding lepton number-violating quadratic mass terms to the inflaton potential of a non-minimally coupled inflation model. The $L$-violating mass terms generate a lepton asymmetry in a complex…

High Energy Physics - Phenomenology · Physics 2023-07-12 Kit Lloyd-Stubbs , John McDonald

Leptogenesis constitues a very simple scenario to achieve the baryon asymmetry that we observe today. It requires only the presence of right handed neutrinos (which arise very naturally in many extensions of the Standard Model) and depends…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Peloso

We present a new mechanism for baryogenesis: at preheating after inflation fermions acquire a varying mass by their coupling to a time dependent field. Their CP-violating mass matrix can generate a charge asymmetry to be transformed into a…

High Energy Physics - Phenomenology · Physics 2017-08-23 Bjorn Garbrecht , Tomislav Prokopec , Michael G. Schmidt

An epoch of Higgs relaxation may occur in the early universe during or immediately following postinflationary reheating. It has recently been pointed out that leptogenesis may occur in minimal extensions of the Standard Model during this…

High Energy Physics - Phenomenology · Physics 2015-08-26 Louis Yang , Lauren Pearce , Alexander Kusenko

We show that accounting for a non-instantaneous reheating phase after inflation can significantly modify the charged lepton Yukawa equilibration temperature in the early Universe. This finding calls for revisiting the role of lepton flavors…

High Energy Physics - Phenomenology · Physics 2026-03-24 Rishav Roshan

In this talk, I shall focus on theories beyond the Standard Model which predict massive neutrinos. Hybrid inflation emerges naturally in these theories: the slow-rolling inflaton field is a gauge singlet which couples with a GUT Higgs field…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rachel Jeannerot

It is well-known that leptogenesis in low energy scale is difficult in the conventional Type-I seesaw mechanism with hierarchical right-handed neutrino masses. We show that in a class of two Higgs doublet model, where one Higgs doublet…

High Energy Physics - Phenomenology · Physics 2011-07-03 Naoyuki Haba , Osamu Seto

We consider a phenomenological extension of the minimal supersymmetric standard model which incorporates non-minimal chaotic inflation, driven by a quartic potential associated with the lightest right-handed sneutrino. Inflation is followed…

High Energy Physics - Phenomenology · Physics 2015-03-17 C. Pallis , N. Toumbas

In this talk, I present a novel and minimal alternative to thermal leptogenesis, which builds upon the assumption that the electroweak gauge bosons are coupled to an axion-like scalar field, as it is, for instance, the case in certain…

High Energy Physics - Phenomenology · Physics 2015-04-01 Kai Schmitz

We consider the introduction of a complex scalar field carrying a global lepton number charge to the Standard Model and the Higgs inflation framework. The conditions are investigated under which this model can simultaneously ensure Higgs…

High Energy Physics - Phenomenology · Physics 2020-11-10 Neil D. Barrie , Akio Sugamoto , Tatsu Takeuchi , Kimiko Yamashita

We study a minimal scenario to realize non-thermal leptogenesis and UV freeze-in of a Standard Model (SM) gauge singlet fermionic dark matter (DM) simultaneously, with inflaton field playing a non-trivial role in their yields. The…

High Energy Physics - Phenomenology · Physics 2021-09-01 Basabendu Barman , Debasish Borah , Rishav Roshan

We consider models for inflation with a stable inflaton. Reheating is achieved through scattering processes such as $\phi \phi \to h h$, where $h$ is the Standard Model Higgs boson. We consider the reheating process in detail and show that…

High Energy Physics - Phenomenology · Physics 2022-02-02 Marcos A. G. Garcia , Yann Mambrini , Keith A. Olive , Sarunas Verner

We show that the process of non-instantaneous reheating during the post-inflationary period can have a sizable impact on the charged lepton Yukawa equilibration temperature in the early Universe. This suggests relooking the effects of…

High Energy Physics - Phenomenology · Physics 2024-01-19 Arghyajit Datta , Rishav Roshan , Arunansu Sil

Leptogenesis is generally challenging to directly test due to the very high energy scales involved. In this work we propose a new probe for leptogenesis with cosmological collider physics. With the example of a cosmological Higgs collider,…

High Energy Physics - Phenomenology · Physics 2022-09-21 Yanou Cui , Zhong-Zhi Xianyu

Thermal leptogenesis in the canonical seesaw model in supersymmetry suffers from the incompatibility of a generic lower bound on the mass scale of the lightest right-handed neutrino and the upper bound on the reheating temperature of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ernest Ma , Narendra Sahu , Utpal Sarkar

We consider a smooth hybrid inflation scenario based on a supersymmetric SU(2)_L x SU(2)_R x U(1)_B-L model. The Higgs triplets involved in the model play a key role in inflation as well as in explaining the observed baryon asymmetry of the…

High Energy Physics - Phenomenology · Physics 2013-05-30 Shaaban Khalil , Qaisar Shafi , Arunansu Sil

Leptogenesis scenarios in supersymmetric hybrid inflation models are considered. Sufficient lepton asymmetry leading to successful baryogenesis can be obtained if the reheat temperature T_r>10^6 GeV and the superpotential coupling parameter…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. N. Senoguz , Q. Shafi