Hypermagnetic helicity evolution in early universe: leptogenesis and hypermagnetic diffusion

Abstract

We study hypermagnetic helicity and lepton asymmetry evolution in plasma of the early Universe before the electroweak phase transition (EWPT) accounting for chirality flip processes via inverse Higgs decays and sphaleron transitions which violate the left lepton number and wash out the baryon asymmetry of the Universe (BAU). In the scenario where the right electron asymmetry supports the BAU alone through the conservation law $B/3-L_{eR}=const$ at temperatures $T>T_{RL}\simeq 10TeV$ the following universe cooling leads to the production of a non-zero left lepton (electrons and neutrinos) asymmetry. This is due to the Higgs decays becoming more faster when entering the equilibrium at $T=T_{RL}$ with the universe expansion, ${\Gamma }_{RL}\sim T>H\sim T^2$, resulting in the parallel evolution of both the right and the left electron asymmetries at $T<T_{RL}$ through the corresponding Abelian anomalies in SM in the presence of a seed hypermagnetic field. The hypermagnetic helicity evolution proceeds in a self-consistent way with the lepton asymmetry growth. The role of sphaleron transitions decreasing the left lepton number turns out to be negligible in given scenario. The hypermagnetic helicity can be a supply for the magnetic one in Higgs phase assuming a strong seed hypermagnetic field in symmetric phase.

23 pages, 6 figures, published in JCAP 10 (2013) 014

References in corpus (7)

• The nuMSM, leptonic asymmetries, and properties of singlet fermions
• Current status of turbulent dynamo theory: From large-scale to small-scale dynamos
• Evolution of Primordial Magnetic Fields from Phase Transitions
• Magnetic Fields from QCD Phase Transitions
• Long-range magnetic fields in the ground state of the Standard Model plasma
• Lepton asymmetry growth in the symmetric phase of an electroweak plasma with hypermagnetic fields versus its washing out by sphalerons
• Lepton asymmetries and the growth of cosmological seed magnetic fields

Cited by in corpus (11)

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• Large-scale magnetic fields can explain the baryon asymmetry of the Universe
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• Leptogenesis and Primordial Magnetic Fields
• Instability of magnetic fields in electroweak plasma driven by neutrino asymmetries
• Generation of hypermagnetic helicity and leptogenesis in early universe
• Chiral Charge Erasure via Thermal Fluctuations of Magnetic Helicity
• Asymmetric Dark Matter and Baryogenesis from Pseudoscalar Inflation
• Leptogenesis in the Symmetric Phase of the Early Universe: Baryon Asymmetry and Hypermagnetic Helicity Evolution
• Nonconservation of lepton current and asymmetry of relic neutrinos
• Generation of the relic neutrino asymmetry in a hot plasma of the early Universe