Thermal-Neutron Activation Cross Sections of Ge and the Isomeric Ratio Rule

The thermal-neutron activation cross sections of ${\mathrm{Ge}}^{74}$ and ${\mathrm{Ge}}^{76}$ were determined. Contrary to indications obtained from previously published neutron cross-section compilations, our results are in agreement with the isomeric ratio rule, which states that the ratio of cross sections for the production of two isomeric states by slow neutron capture is such that the isomeric state with spin close to that of the compound nucleus is favored.