English

Primordial Deuterium Abundance Measurements

Astrophysics 2007-05-23 v1

Abstract

Deuterium abundances measured recently from QSO absorption-line systems lie in the range from 3 10^{-5} to 3 10^{-4}, which shed some questions on standard big bang theory. We show that this discordance may simply be an artifact caused by inadequate analysis ignoring spatial correlations in the velocity field in turbulent media. The generalized procedure (accounting for such correlations) is suggested to reconcile the D/H measurements. An example is presented based on two high-resolution observations of Q1009+2956 (low D/H) [1,2] and Q1718+4807 (high D/H) [8,9]. We show that both observations are compatible with D/H = 4.1 - 4.6 10^{-5}, and thus support SBBN. The estimated mean value <D/H> = 4.4 10^{-5} corresponds to the baryon-to-photon ratio during SBBN eta = 4.4 10^{-10} which yields the present-day baryon density Omega_b h^2 = 0.015.

Keywords

Cite

@article{arxiv.astro-ph/9712305,
  title  = {Primordial Deuterium Abundance Measurements},
  author = {Sergei A. Levshakov and Wilhelm H. Kegel and Fumio Takahara},
  journal= {arXiv preprint arXiv:astro-ph/9712305},
  year   = {2007}
}

Comments

4 pages, 1 Postscript figure, res.sty and ceu.sty files, to appear in "Particle Cosmology", eds. K. Sato, T. Yanagida and T. Shiromizu (Universal Academy Press, Inc. : Tokyo)