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Title: Lepton asymmetry, neutrino spectral distortions, and big bang nucleosynthesis

In this paper, we calculate Boltzmann neutrino energy transport with self-consistently coupled nuclear reactions through the weak-decoupling-nucleosynthesis epoch in an early universe with significant lepton numbers. We find that the presence of lepton asymmetry enhances processes which give rise to nonthermal neutrino spectral distortions. Our results reveal how asymmetries in energy and entropy density uniquely evolve for different transport processes and neutrino flavors. The enhanced distortions in the neutrino spectra alter the expected big bang nucleosynthesis light element abundance yields relative to those in the standard Fermi-Dirac neutrino distribution cases. These yields, sensitive to the shapes of the neutrino energy spectra, are also sensitive to the phasing of the growth of distortions and entropy flow with time/scale factor. Finally, we analyze these issues and speculate on new sensitivity limits of deuterium and helium to lepton number.
 [1] ;  [2] ;  [3] ;  [4]
  1. Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Physics
  2. Univ. of California, San Diego, CA (United States). Dept. of Physics
  3. Univ. of California, San Diego, CA (United States). Dept. of Physics. Dept. of Physics and Biophysics
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2470-0010
Grant/Contract Number:
AC52-06NA25396; AC02-05CH11231; PHY-1307372
Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 95; Journal Issue: 6; Journal ID: ISSN 2470-0010
American Physical Society (APS)
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE Office of Science (SC); USDOE National Nuclear Security Administration (NNSA); USDOE Laboratory Directed Research and Development (LDRD) Program; National Science Foundation (NSF)
Contributing Orgs:
Univ. of Michigan, Ann Arbor, MI (United States)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; cosmological parameters from CMBR, big bang nucleosynthesis, cosmological neutrinos, neutrino lepton numbers, neutrino theory
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1345690