NEUTRON-CAPTURE CROSS-SECTION OF N-15 AT STELLAR ENERGIES

The neutron capture rate on N-15 may be of considerable importance for s-process nucleosynthesis in red giants as well as for the nucleosynt hesis in inhomogeneous big bang scenarios. We measured the reaction cr oss section of N-15(n, gamma) N-16 at the Forschungszentrum Karlsruhe with a fast cyclic neutron activation technique at laboratory neutron energies of 25, 152, and 370 keV. Direct capture and shell model calcu lations were per formed to interpret the results. The presented reacti on rate is 30-50 % smaller than the previously used theoretical rates.