CL-36 (N,P)S-36 CROSS-SECTION FROM 25 MEV TO 800 KEV AND THE NUCLEOSYNTHESIS OF THE RARE ISOTOPE S-36

We have measured the (Cl(n,p)S)-Cl-36-S-36 cross section from thermal energy to approximately 800 keV. Parameters for eight resonances betwe en 900 eV and 70 keV were determined in a multilevel fit to our data w hich also included information from published (S(p, gamma)Cl)-S-36-Cl- 37 measurements. The (Cl(n,p)S)-Cl-36-S-36 reaction can play a critica l role in the production of the rare isotope S-36 in explosive nucleos ynthesis and s-process calculations. The astrophysical rate for this r eaction was calculated from our measured cross sections and was found to be significantly smaller than the theoretical rate used in previous nucleosynthesis calculations. We discuss the impact of this result on the nucleosynthesis of S-36.