Toward correction-free 8Li(α, n)11B data at the Gamow energy of explosive nucleosynthesis

The 8Li+4He -> 11B+n reaction inside the center-of-mass energy region Ecm = 0.5--2.5 MeV, corresponding to the temperature range T9 = 1--5, is of relevant interest in the fields of nuclear cosmology and nuclear astrophysics. In the context of Big Bang nucleosynthesis, it has been invoked to overcome the A = 8 mass gap; in r-process nucleosynthesis, it is considered a candidate precursor of seed nuclei. In this experimental work, the cross section, summed over all 11B final bound states, at the energy of 1.05 MeV in the center-of-mass system, is investigated by a correction-free projectile-correlated inclusive neutron measurement. The radioactive 8Li beam delivered by the EXCYT facility at LNS-Catania is used to induce the inverse-kinematics reaction process. A zero-energy-threshold 4 Delta *p detection system is used. Thanks to the improved experimental and analysis procedures, the result obtained in this work represents a strong argument to reopen the debate on the magnitude of the 8Li( Delta *a, n)11B reaction rate in explosive astrophysical environments.