Spectator and lepton flavor effects in leptogenesis

• Grant number: 24/13078-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2024
• End date: July 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Physics - Elementary Particle Physics and Fields
• Principal Investigator: Chee Sheng Fong
• Grantee: Letícia Uglar Motta
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil
• Associated research grant: 19/11197-6 - Precision test of baryogenesis, AP.JP

Abstract

Baryogenesis through leptogenesis is an attractive and economical framework which explains both small neutrino mass and baryon-antibaryon asymmetry of the Universe. It could occur in the early Universe anywhere from 100 GeV up to Grand Unification Theories scale. In this window, besides the particles directly involved in leptogenesis, there are many other particles in the thermal bath which could either be in or out of thermal equilibrium depending on the temperature. The effects pertaining to lepton flavors are known as lepton flavor effects while others are collectively known as spectator effects. These effects can be neatly taken into account applying the symmetry method.