Solution to Big-Bang Nucleosynthesis in Hybrid Axion Dark Matter Model

Physics Letters B (Impact Factor: 4.57). 02/2012; 718(3). DOI: 10.1016/j.physletb.2012.11.007
Source: arXiv

ABSTRACT Following a recent suggestion of axion cooling of photons between the
nucleosynthesis and recombination epochs in the Early Universe, we investigate
a hybrid model with both axions and relic supersymmetric particles. In this
model we demonstrate that the 7Li abundance can be consistent with observations
without destroying the important concordance of deuterium abundance.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Standard Big Bang Nucleosynthesis at the baryon density determined by the microwave anisotropy spectrum predicts an excess of \li7 compared to observations by a factor of 4-5. In contrast, BBN predictions for D/H are somewhat below (but within ~2 \sigma) of the weighted mean of observationally determined values from quasar absorption systems. Solutions to the \li7 problem which alter the nuclear processes during or subsequent to BBN, often lead to a significant increase in the deuterium abundance consistent with the highest values of D/H seen in absorption systems. Furthermore, the observed D/H abundances show considerable dispersion. Here, we argue that those systems with D/H \simeq 4 \times 10^{-5} may be more representative of the primordial abundance and as a consequence, those systems with lower D/H would necessarily have been subject to local processes of deuterium destruction. This can be accounted for by models of cosmic chemical evolution able to destroy in situ Deuterium due to the fragility of this isotope.
    Monthly Notices of the Royal Astronomical Society 03/2012; 426(2). · 5.52 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Using the primordial helium abundance, an upper limit to the magnetic moments for Dirac neutrinos had been provided by imposing restrictions on the number of the additional helicity states. Considering non-thermal photons produced in the decay of the heavy sterile mass eigenstates due to the neutrino magnetic moment, we explore the constraints imposed by the observed abundances of all the light elements produced during the Big Bang nucleosynthesis.
    Physical review D: Particles and fields 03/2013; 87(8).
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The abundance of lithium-7 confronts cosmology with a long lasting problem between the predictions of standard big bang nucleosynthesis and the baryonic density determined from the cosmic microwave background observations. This article investigates the influence of the existence of a mirror world, focusing on models in which neutrons can oscillate into mirror neutrons. Such a mechanism allows for an effective late time neutron injection, which induces an increase of the destruction of beryllium-7, due to an increase of the neutron capture, and then a decrease of the final lithium-7 abundance. Big bang nucleosynthesis sets constraints on the oscillation time between the two types of neutron and the possibility for such a mechanism to solve, or alleviate, the lithium problem is emphasized.
    Physical review D: Particles and fields 03/2013; 87(12).

Full-text (2 Sources)

Available from
Jun 4, 2014