Neutron-Capture Cross Sections of the Europium and Lutetium Isotopes from 0.01 to 10 eV

Absolute neutron-capture cross-section measurements from 0.01 to 10 eV employing a Moxon-Rae detector and conventional time-of-flight techniques are described. For the calculation of multiple-scattering and gamma-ray attenuation effects in samples, new improved methods were developed. Cross-section curves were evaluated for the elements europium and lutetium as well as for the isotopes ¹⁵¹Eu, ¹⁵³Eu, ¹⁷⁵Lu, and ¹⁷⁶Lu. The cross sections could be determined to an accuracy of better than 5%; however, for some resonance cross sections the total error increases up to 10%.