Neutron Capture Cross Sections ofC13andO16

Measurements have been made of the radiative widths of the lowest energy resonances in ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$. Maxwellian-averaged capture cross sections calculated for $kT=30\mathrm{}$ keV indicate that ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ could not have been significant neutron poisons in $s$-process nucleosynthesis.