Cross-section Measurement of the Cosmologically Relevant 7 Be(n, α) 4 He Reaction over a Broad Energy Range in a Single Experiment

Abstract

Studying interactions of radioactive ions with neutrons is particularly demanding and has been performed only in a few cases. Some of these interactions are crucial in several astrophysical contexts. In the present work, the case of the 7 Be destruction induced by the (n, α ) reaction is investigated at the energies typical of the primordial nucleosynthesis by means of the Trojan Horse Method applied to the 2 H( 7 Be, αα )p quasi-free reaction. The 7 Be(n, α ) 4 He cross-section has been measured in a single experiment from ∼2 MeV down to cosmological energies. The corresponding deduced reaction rate has been adopted to evaluate the impact on big bang nucleosynthesis and on the lithium problem.