A new constraint on primordial lepton flavour asymmetries

Abstract

A chiral chemical potential present in the early universe can source helical hypermagnetic fields through the chiral plasma instability. If these hypermagnetic fields survive until the electroweak phase transition, they source a contribution to the baryon asymmetry of the universe. In this letter, we demonstrate that lepton flavour asymmetries above $|\mu |/T\sim 9\times 10^{-3}$ trigger this mechanism even for vanishing total lepton number. This excludes the possibility of such large lepton flavour asymmetries present at temperatures above $10^6$ GeV, setting a constraint which is about two orders of magnitude stronger than the current CMB and BBN limits.

4 pages, matches journal version

References in corpus (22)

• The Chiral Magnetic Effect
• Primordial Nucleosynthesis: from precision cosmology to fundamental physics
• Quantum Anomalies in Dense Matter
• Evolution of Primordial Magnetic Fields from Phase Transitions
• EMPRESS. VIII. A New Determination of Primordial He Abundance with Extremely Metal-Poor Galaxies: A Suggestion of the Lepton Asymmetry and Implications for the Hubble Tension
• Evolution of the Baryon Asymmetry through the Electroweak Crossover in the Presence of a Helical Magnetic Field
• Baryon Asymmetry and Gravitational Waves from Pseudoscalar Inflation
• The turbulent chiral-magnetic cascade in the early universe
• Relic density of neutrinos with primordial asymmetries
• Cosmological lepton asymmetry with a nonzero mixing angle θ_{13}
• Improved constraints on lepton asymmetry from the cosmic microwave background
• Indications for a Nonzero Lepton Asymmetry from Extremely Metal-Poor Galaxies
• Primordial lepton asymmetries in the precision cosmology era: Current status and future sensitivities from BBN and the CMB
• Lepton Asymmetric Universe
• Primordial neutrino asymmetry evolution with full mean-field effects and collisions
• Baryogenesis from an Earlier Phase Transition
• Updating non-standard neutrinos properties with Planck-CMB data and full-shape analysis of BOSS and eBOSS galaxies
• Hubble tension in lepton asymmetric cosmology with an extra radiation
• Wash-in leptogenesis after axion inflation
• Baryon isocurvature constraints on the primordial hypermagnetic fields
• Leptoflavorgenesis: baryon asymmetry of the Universe from lepton flavor violation
• Large Lepton Asymmetry for Small Baryon Asymmetry and Warm Dark Matter

Cited by in corpus (8)

• Constraints on primordial lepton asymmetries with full neutrino transport
• Large Neutrino Asymmetry from TeV Scale Leptogenesis
• Lepton Flavor Asymmetries: from the early Universe to BBN
• Pseudo-Dirac Neutrinos and Relic Neutrino Matter Effect on the High-energy Neutrino Flavor Composition
• Relic Gravitational Waves from the Chiral Plasma Instability in the Standard Cosmological Model
• A lower bound on the right-handed neutrino mass from wash-in leptogenesis
• A trial to understand the supersymmetry relations through extension of the second quantized fermion and boson fields, either to strings or to odd dimensional spaces
• Constraints on the lepton asymmetry from DESI DR2 BAO data