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We investigate the possibility that inhomogeneous nucleosynthesis may eventually be used to explain the abundances of li6, be9 and B in population II stars. The present work differs from previous studies in that we have used a more extensive reaction network. It is demonstrated that in the simplest scenario the abundances of the light elements with $Ale7$ constrain the separation of inhomogeneities to sufficiently small scales that the model is indistinguishable from homogeneous nucleosynthesis and that the abundances of li6, be9 and B are then below observations by several orders of magnitude. This conclusion does not depend on the li7 constraint. We also examine alternative scenarios which involve a post-nucleosynthesis reprocessing of the light elements to reproduce the observed abundances of Li and B, while allowing for a somewhat higher baryon density (still well below the cosmological critical density). Future B/H measurements may be able to exclude even this exotic scenario and further restrict primordial nucleosynthesis to approach the homogeneous model conclusions.
We examine effects on primordial nucleosynthesis from a truly random spatial distribution in the baryon-to-photon ratio ($eta$). We generate stochastic fluctuation spectra characterized by different spectral indices and root-mean-square fluctuation a
We reassess the problem of the production and evolution of the light elements Li, Be and B and of their isotopes in the Milky Way, in the light of new observational and theoretical developments. The main novelty is the introduction of a new scheme fo
We present an up-to-date review of Big Bang Nucleosynthesis (BBN). We discuss the main improvements which have been achieved in the past two decades on the overall theoretical framework, summarize the impact of new experimental results on nuclear rea
A new accurate evaluation of primordial light nuclei abundances is presented. The proton to neutron conversion rates have been corrected to take into account radiative effects, finite nucleon mass, thermal and plasma corrections. The theoretical uncertainty on 4He is so reduced to the order of 0.1%.
We have modified the standard code for primordial nucleosynthesis to include the effect of the slight heating of neutrinos by $e^pm$ annihilations. There is a small, systematic change in the $^4$He yield, $Delta Y simeq +1.5times 10^{-4}$, which is i