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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 7Be 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 2H(7Be, αα)p quasi-free reaction. The 7Be(n, α)4He 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. [ABSTRACT FROM AUTHOR]

The observational 19F abundance in stellar environments systematically exceeds the predicted one, thus representing one of the unsolved challenges for stellar modeling. It is therefore clear that further investigation is needed in this field. In this work, we focus our attention on the measurement of the reaction in the astrophysical energy range, between 0.2 and 0.8 MeV (far below the Coulomb barrier, 3.8 MeV), as it represents the main destruction channel in He-rich environments. The lowest energy at which this reaction has been studied with direct measurements is ∼0.66 MeV, covering only the upper tail of the Gamow window, causing the reaction-rate evaluation to be based on extrapolation. To investigate lower energies, the reaction has been studied by means of the Trojan horse method, applied to the quasi-free reaction at Ebeam = 6 MeV. The indirect cross section of the reaction at energies ≲1 MeV was extracted, fully covering the astrophysical region of interest and overlapping existing direct data for normalization. Several resonances have been detected for the first time inside the Gamow window. The reaction rate has been calculated, showing an increase up to a factor of 4 with respect to the literature at astrophysical temperatures. This might lead to potential major astrophysical implications. [ABSTRACT FROM AUTHOR]