Neutron capture cross section of 15N at stellar energies

The neutron capture rate on 15N may be of considerable importance for s-process nucleosynthesis in red giants as well as for the nucleosynthesis in inhomogeneous big bang scenarios. We measured the reaction cross section of 15N(n,γ)16N 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 calculations were performed to interpret the results. The presented reaction rate is 30 endash 50% smaller than the previously used theoretical rates. copyright 1996 The American Physical Society