skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''

Abstract

This is a reply to Rauscher [Phys. Rev. D 75, 068301 (2007)]. We studied heavy element production in the high baryon density region in the early universe [Phys. Rev. D 72, 123505 (2005)]. However, it is claimed by Rauscher [Phys. Rev. D 75, 068301 (2007)] that a small scale but high baryon density region contradicts observations for the light element abundance or, in order not to contradict the observations, the high density region must be so small that it cannot affect the present heavy element abundance. In this paper, we study big bang nucleosynthesis in the high baryon density region and show that in certain parameter spaces it is possible to produce enough of the heavy element without contradiction to cosmic microwave background and light element observations.

Authors:
; ; ;  [1];  [2];  [2];  [2];  [2]
  1. Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
21020222
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.068302; (c) 2007 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; BARYONS; COSMOLOGICAL MODELS; COSMOLOGY; DENSITY; ELEMENT ABUNDANCE; NUCLEOSYNTHESIS; RELICT RADIATION; SPACE; UNIVERSE

Citation Formats

Matsuura, Shunji, Fujimoto, Shin-ichirou, Hashimoto, Masa-aki, Sato, Katsuhiko, Department of Electronic Control, Kumamoto National College of Technology, Kumamoto 861-1102, Department of Physics, School of Sciences, Kyushu University, Fukuoka 810-8560, Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, and Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033. Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.068302.
Matsuura, Shunji, Fujimoto, Shin-ichirou, Hashimoto, Masa-aki, Sato, Katsuhiko, Department of Electronic Control, Kumamoto National College of Technology, Kumamoto 861-1102, Department of Physics, School of Sciences, Kyushu University, Fukuoka 810-8560, Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, & Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033. Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''. United States. doi:10.1103/PHYSREVD.75.068302.
Matsuura, Shunji, Fujimoto, Shin-ichirou, Hashimoto, Masa-aki, Sato, Katsuhiko, Department of Electronic Control, Kumamoto National College of Technology, Kumamoto 861-1102, Department of Physics, School of Sciences, Kyushu University, Fukuoka 810-8560, Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, and Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033. Thu . "Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''". United States. doi:10.1103/PHYSREVD.75.068302.
@article{osti_21020222,
title = {Reply to 'Comment on 'Heavy element production in inhomogeneous big bang nucleosynthesis''},
author = {Matsuura, Shunji and Fujimoto, Shin-ichirou and Hashimoto, Masa-aki and Sato, Katsuhiko and Department of Electronic Control, Kumamoto National College of Technology, Kumamoto 861-1102 and Department of Physics, School of Sciences, Kyushu University, Fukuoka 810-8560 and Department of Physics, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 and Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033},
abstractNote = {This is a reply to Rauscher [Phys. Rev. D 75, 068301 (2007)]. We studied heavy element production in the high baryon density region in the early universe [Phys. Rev. D 72, 123505 (2005)]. However, it is claimed by Rauscher [Phys. Rev. D 75, 068301 (2007)] that a small scale but high baryon density region contradicts observations for the light element abundance or, in order not to contradict the observations, the high density region must be so small that it cannot affect the present heavy element abundance. In this paper, we study big bang nucleosynthesis in the high baryon density region and show that in certain parameter spaces it is possible to produce enough of the heavy element without contradiction to cosmic microwave background and light element observations.},
doi = {10.1103/PHYSREVD.75.068302},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
  • The work of Matsuura et al. [Phys. Rev. D 72, 123505 (2005)] claims that heavy nuclei could have been produced in a combined p- and r-process in very high baryon density regions of an inhomogeneous big bang. However, they do not account for observational constraints and previous studies which show that such high baryon density regions did not significantly contribute to big bang abundances.
  • We present a new astrophysical site of the big bang nucleosynthesis (BBN) that are very peculiar compared with the standard BBN. Some models of the baryogenesis suggest that very high baryon density regions were formed in the early universe. On the other hand, recent observations suggest that heavy elements already exist in high red-shifts and the origin of these elements become a big puzzle. Motivated by these, we investigate BBN in very high baryon density regions. BBN proceeds in proton-rich environment, which is known to be like the p-process. However, by taking very heavy nuclei into account, we find thatmore » BBN proceeds through both the p-process and the r-process simultaneously. P-nuclei such as {sup 92}Mo, {sup 94}Mo, {sup 96}Ru, {sup 98}Ru whose origin is not well known are also synthesized.« less
  • We review recent lattice QCD results for the surface tension at the finite temperature quark-hadron phase transition and discuss their implications on the possible scale of inhomogeneities. In the quenched approximation the average distance between nucleating centers is smaller than the diffusion length of a proton, so that inhomogeneities are washed out by the time nucleosynthesis sets in. At present lattice results are inconclusive when dynamical fermions are included.
  • The neutron capture on {sup 17}O and {sup 18}O may play an important role for the nucleosynthesis of light isotopes A {le} 20 in the neutron rich zones of an inhomogencous early universe. To investigate these effects we measured the reaction rates of {sup 17}O(n,{alpha}){sup 14}C and {sup 18}O(n,{gamma}){sup 19}O. The experimental results and the resulting reaction rates will be presented. The influence of these reactions for the nucleosynthesis of light ions and the general reaction flow in the mass region A< 20 will be discussed.
  • We have studied finite temperature corrections to the baryon transport cross sections and diffusion coefficients. These corrections are based upon our recently computed renormalized electron mass and modified state density due to the background thermal bath in the early universe. It is found that the optimum nucleosynthesis yields computed using our diffusion coefficients shift to longer distance scales by a factor of about 3. We also find that the primordial {sup 4}He abundance decreases by {Delta}Y{sub p}{approx_equal}0.01 while {ital D} and {sup 7}Li increase. The effects of these results on constraints from primordial nucleosynthesis are discussed. In particular, we findmore » that a large baryonic contribution to the closure density ({Omega}{sub b}h{sub 50}{sup 2}{approx_lt}0.4) may be allowed in inhomogeneous models corrected for finite temperature. {copyright} {ital 1998} {ital The American Physical Society}« less