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arXiv · 0911.2585

Solving the large discrepancy between inclusive and exclusive measurements of the ${}^8{\rm Li}+{}^4{\rm He}\to{}^{11}{\rm B}+n$ reaction cross section at astrophysical energies

M. La Cognata
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Abstract

A solution of the large discrepancy existing between inclusive and exclusive measurements of the ${}^8{\rm Li}+{}^4{\rm He}\to{}^{11}{\rm B}+n$ reaction cross section at $E_{cm} <3$ MeV is evaluated. This problem has profound astrophysical relevance for this reaction is of great interest in Big-Bang and r-process nucleosynthesis. By means of a novel technique, a comprehensive study of all existing ${}^8{\rm Li}+{}^4{\rm He}\to{}^{11}{\rm B}+n$ cross section data is carried out, setting up a consistent picture in which all the inclusive measurements provide the reliable value of the cross section. New unambiguous signatures of the strong branch pattern non-uniformities, near the threshold of higher ${}^{11}{\rm B}$ excited levels, are presented and their possible origin, in terms of the cluster structure of the involved excited states of ${}^{11}{\rm B}$ and ${}^{12}{\rm B}$ nuclei, is discussed.

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M. La Cognata. 2009-11-13. Solving the large discrepancy between inclusive and exclusive measurements of the ${}^8{\rm Li}+{}^4{\rm He}\to{}^{11}{\rm B}+n$ reaction cross section at astrophysical energies. https://doi.org/10.1088/0004-637x/706/2/l251

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