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Primordial Nucleosynthesis and the Abundances of Beryllium and Boron

David Thomas·David N. Schramm·Keith A. Olive·Brian D. Fields
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Abstract

The ability to now make measurements of Be and B as well as put constraints on \lisix\ abundances in metal-poor stars has led to a detailed reexamination of Big Bang Nucleosynthesis in the $A\groughly6$ regime. The nuclear reaction network has been significantly expanded with many new rates added. It is demonstrated that although a number of $A>7$ reaction rates are poorly determined, even with extreme values chosen, the standard homogeneous model is unable to produce significant yields (Be/H and B/H $<10^{-17}$ when $A\le7$ abundances fit) above $A=7$ and the \liseven/\lisix\ ratio always exceeds 500. We also preliminarily explore inhomogeneous models, such as those inspired by a first order quark-hadron phase transition, where regions with high neutron/proton ratios can allow some leakage up to $A>7$. However models that fit the $A\le7$ abundances still seem to have difficulty in obtaining significant $A>7$ yields.

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David Thomas, David N. Schramm, Keith A. Olive, Brian D. Fields. 1992-06-18. Primordial Nucleosynthesis and the Abundances of Beryllium and Boron. https://doi.org/10.1086/172469

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