Constraining the universal lepton asymmetry

  title={Constraining the universal lepton asymmetry},
  author={Vimal Simha and Gary Steigman},
  journal={Journal of Cosmology and Astroparticle Physics},
  • V. Simha, G. Steigman
  • Published 1 June 2008
  • Physics
  • Journal of Cosmology and Astroparticle Physics
The relic cosmic background neutrinos accompanying the cosmic microwave background (CMB) photons may hide a universal lepton asymmetry orders of magnitude larger than the universal baryon asymmetry. At present, the only direct way to probe such an asymmetry is through its effect on the abundances of the light elements produced during primordial nucleosynthesis. The relic light element abundances also depend on the baryon asymmetry, parameterized by the baryon density parameter () and on the… 

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