Big bang nucleosynthesis constraints on primordial magnetic fields

Peter J. Kernan, Glenn D. Starkman, Tanmay Vachaspati

Research output: Contribution to journalArticle

61 Citations (Scopus)

Abstract

We reanalyze the effect of magnetic fields in BBN, incorporating several features which were omitted in previous analyses. We find that the effects of coherent magnetic fields on the weak interaction rates and the electron thermodynamic functions (ρe , Pe , and dρ/dT γ) are unimportant in comparison with the contribution of the magnetic field energy density in BBN. As a consequence the effect of including magnetic fields in BBN is well approximated numerically by treating the additional energy density as an effective neutrino number. A conservative upper bound on the primordial magnetic field, parametrized as ζ=2eBrms/(Tv 2), is ζ≤2(ρB<0.27ρv). This bound can be stronger than the conventional bound coming from the Faraday rotation measures of distant quasars if the cosmological magnetic field is generated by a causal mechanism.

Original languageEnglish (US)
Pages (from-to)7207-7214
Number of pages8
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume54
Issue number12
StatePublished - Dec 15 1996
Externally publishedYes

Fingerprint

nuclear fusion
Magnetic Field
magnetic fields
Energy Density
flux density
Quasars
Faraday effect
Neutrinos
quasars
Thermodynamics
neutrinos
Electron
Upper bound
thermodynamics
Interaction
electrons

ASJC Scopus subject areas

  • Mathematical Physics
  • Physics and Astronomy(all)
  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

Big bang nucleosynthesis constraints on primordial magnetic fields. / Kernan, Peter J.; Starkman, Glenn D.; Vachaspati, Tanmay.

In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 54, No. 12, 15.12.1996, p. 7207-7214.

Research output: Contribution to journalArticle

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