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Title: Inhomogeneous big bang nucleosynthesis revisited

Abstract

We reanalyze the allowed parameters for inhomogeneous big bang nucleosynthesis in light of the WMAP constraints on the baryon-to-photon ratio {eta} and a recent measurement which has set the neutron lifetime to be 878.5{+-}0.7{+-}0.3 sec. For a set baryon-to-photon ratio {eta} the new lifetime reduces the mass fraction of {sup 4}He by 0.0015 but does not significantly change the abundances of other isotopes. This enlarges the region of concordance between {sup 4}He and deuterium in the parameter space of {eta} and the IBBN distance scale r{sub i}. The {sup 7}Li abundance can be brought into concordance with observed {sup 4}He and deuterium abundances by using depletion factors as high as 9.3. The WMAP constraints, however, severely limit the allowed comoving (T=100 GK) inhomogeneity distance scale to r{sub i}{approx_equal}(1.3-2.6)x10{sup 5} cm.

Authors:
; ;  [1];  [2];  [3]
  1. Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29631 (United States) and National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
  2. (Japan) and Department of Astronomy, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo 113-0033 (Japan)
  3. (United States) and National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
Publication Date:
OSTI Identifier:
20782872
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.73.083501; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGY; DEUTERIUM; DISTANCE; ELEMENT ABUNDANCE; HELIUM 4; LIFETIME; LITHIUM 7; NEUTRONS; NUCLEOSYNTHESIS; PHOTONS

Citation Formats

Lara, Juan F., Kajino, Toshitaka, Mathews, Grant J., National Astronomical Observatory and Graduate University for Advanced Studies, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, and University of Notre Dame, Center for Astrophysics, Notre Dame, Indiana 46556. Inhomogeneous big bang nucleosynthesis revisited. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.083501.
Lara, Juan F., Kajino, Toshitaka, Mathews, Grant J., National Astronomical Observatory and Graduate University for Advanced Studies, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, & University of Notre Dame, Center for Astrophysics, Notre Dame, Indiana 46556. Inhomogeneous big bang nucleosynthesis revisited. United States. doi:10.1103/PHYSREVD.73.083501.
Lara, Juan F., Kajino, Toshitaka, Mathews, Grant J., National Astronomical Observatory and Graduate University for Advanced Studies, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, and University of Notre Dame, Center for Astrophysics, Notre Dame, Indiana 46556. Sat . "Inhomogeneous big bang nucleosynthesis revisited". United States. doi:10.1103/PHYSREVD.73.083501.
@article{osti_20782872,
title = {Inhomogeneous big bang nucleosynthesis revisited},
author = {Lara, Juan F. and Kajino, Toshitaka and Mathews, Grant J. and National Astronomical Observatory and Graduate University for Advanced Studies, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 and University of Notre Dame, Center for Astrophysics, Notre Dame, Indiana 46556},
abstractNote = {We reanalyze the allowed parameters for inhomogeneous big bang nucleosynthesis in light of the WMAP constraints on the baryon-to-photon ratio {eta} and a recent measurement which has set the neutron lifetime to be 878.5{+-}0.7{+-}0.3 sec. For a set baryon-to-photon ratio {eta} the new lifetime reduces the mass fraction of {sup 4}He by 0.0015 but does not significantly change the abundances of other isotopes. This enlarges the region of concordance between {sup 4}He and deuterium in the parameter space of {eta} and the IBBN distance scale r{sub i}. The {sup 7}Li abundance can be brought into concordance with observed {sup 4}He and deuterium abundances by using depletion factors as high as 9.3. The WMAP constraints, however, severely limit the allowed comoving (T=100 GK) inhomogeneity distance scale to r{sub i}{approx_equal}(1.3-2.6)x10{sup 5} cm.},
doi = {10.1103/PHYSREVD.73.083501},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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