Measurement and resonance analysis of the 33S (n, alpha) 30Si cross section at the CERN n_TOF facility in the energy region from 10 to 300 keV

The 33S(n,a)30Si cross section has been measured at the neutron time-of-flight (n_TOF) facility at CERN in the neutron energy range from 10 to 300 keV relative to the 10B(n,a)7Li cross-section standard. Both reactions were measured simultaneously with a set of micromegas detectors. The flight path of 185 m has allowed us to obtain the cross section with high-energy resolution. An accurate description of the resonances has been performed by means of the multilevel multichannel R-matrix code SAMMY. The results show a significantly higher area of the biggest resonance (13.45 keV) than the unique high-resolution (n,a) measurement. The new parametrization of the 13.45-keV resonance is similar to that of the unique transmission measurement. This resonance is a matter of research in neutron-capture therapy. The 33S(n,a)30Si cross section has been studied in previous works because of its role in the production of 36S in stars, which is currently overproduced in stellar models compared to observations.Postprint (published version