Cross section of $^{36}S(n,γ)^{37}S$

Abstract

At the Karlsruhe pulsed 3.75 MV Van de Graaff accelerator the $^{36}S(n,γ)^{37}S(5.05 min)$ cross section was measured by the fast cyclic activation technique via the 3.103 MeV $γ$-ray line of the $^{37}$S-decay. Samples of elemental sulfur enriched in $^{36}$S by 5.933 % were irradiated between two gold foils which served as capture standards. The capture cross section was measured at the neutron energies 25, 151, 176, and 218 keV, respectively. The $^{36}S(n,γ)^{37}S$-cross section in the thermonuclear and thermal energy range has been calculated using the direct-capture (DC) model combined with the folding procedure used for the determination of the potentials. The non-resonant experimental data for this reaction can be reproduced excellently using this method. The input parameters of the DC-calculation (masses, Q-values, nuclear density distributions, spectroscopic factors, spin-parity assignments and excitation energies of the low-lying states of the residual nucleus) have been taken from the available experimental data.