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Title: Producing the deuteron in stars: anthropic limits on fundamental constants

Abstract

Stellar nucleosynthesis proceeds via the deuteron (D), but only a small change in the fundamental constants of nature is required to unbind it. Here, we investigate the effect of altering the binding energy of the deuteron on proton burning in stars. We find that the most definitive boundary in parameter space that divides probably life-permitting universes from probably life-prohibiting ones is between a bound and unbound deuteron. Due to neutrino losses, a ball of gas will undergo rapid cooling or stabilization by electron degeneracy pressure before it can form a stable, nuclear reaction-sustaining star. We also consider a less-bound deuteron, which changes the energetics of the pp and pep reactions. The transition to endothermic pp and pep reactions, and the resulting beta-decay instability of the deuteron, do not seem to present catastrophic problems for life.

Authors:
;  [1]
  1. Sydney Institute for Astronomy, School of Physics, A28, The University of Sydney, New South Wales, 2006 Australia (Australia)
Publication Date:
OSTI Identifier:
22676091
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 07; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BETA DECAY; COOLING; DECAY INSTABILITY; DEUTERONS; ELECTRONS; FUNDAMENTAL CONSTANTS; LOSSES; NEUTRINOS; NUCLEAR REACTIONS; NUCLEOSYNTHESIS; PARTICLE PRODUCTION; PROTONS; SPACE; STABILIZATION; STARS; UNIVERSE

Citation Formats

Barnes, Luke A., and Lewis, Geraint F., E-mail: luke.barnes@sydney.edu.au, E-mail: gfl@physics.usyd.edu.au. Producing the deuteron in stars: anthropic limits on fundamental constants. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/07/036.
Barnes, Luke A., & Lewis, Geraint F., E-mail: luke.barnes@sydney.edu.au, E-mail: gfl@physics.usyd.edu.au. Producing the deuteron in stars: anthropic limits on fundamental constants. United States. doi:10.1088/1475-7516/2017/07/036.
Barnes, Luke A., and Lewis, Geraint F., E-mail: luke.barnes@sydney.edu.au, E-mail: gfl@physics.usyd.edu.au. Sat . "Producing the deuteron in stars: anthropic limits on fundamental constants". United States. doi:10.1088/1475-7516/2017/07/036.
@article{osti_22676091,
title = {Producing the deuteron in stars: anthropic limits on fundamental constants},
author = {Barnes, Luke A. and Lewis, Geraint F., E-mail: luke.barnes@sydney.edu.au, E-mail: gfl@physics.usyd.edu.au},
abstractNote = {Stellar nucleosynthesis proceeds via the deuteron (D), but only a small change in the fundamental constants of nature is required to unbind it. Here, we investigate the effect of altering the binding energy of the deuteron on proton burning in stars. We find that the most definitive boundary in parameter space that divides probably life-permitting universes from probably life-prohibiting ones is between a bound and unbound deuteron. Due to neutrino losses, a ball of gas will undergo rapid cooling or stabilization by electron degeneracy pressure before it can form a stable, nuclear reaction-sustaining star. We also consider a less-bound deuteron, which changes the energetics of the pp and pep reactions. The transition to endothermic pp and pep reactions, and the resulting beta-decay instability of the deuteron, do not seem to present catastrophic problems for life.},
doi = {10.1088/1475-7516/2017/07/036},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 07,
volume = 2017,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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