Neutron Activation at 195 kev

Neutron activation cross sections have been measured at 195 kev (50 kev energy spread) for about 30 isotopes, by absolute gamma counting. Absolute calibration was effected by determining the RdTh-${\mathrm{D}}_2$O neutron source strength with a flat response $4\pi$ graphite sphere neutron counter, and irradiating indium in the form of a thin, uniform, spherical shell. The results are in general agreement with those of other investigators. The 25-kev activation cross sections of ${\mathrm{Pr}}^{141}$, ${\mathrm{Zr}}^{94}$, ${\mathrm{Ga}}^{71}$, and ${\mathrm{Pd}}^{108}$ have been revised.