Short-Lived Fission Products. II. Cs139 and Cs140

Abstract
Half‐life values have been obtained for Cs139 and Cs140 by extraction of the Ba descendent activities from cesium silicotungstate precipitates. The half‐life of Cs139 was found to be 9.5±0.2 min. by this technique and that of Cs140, 66±2 sec. The value for the Cs139 half‐life was confirmed by observation of a Cs sample isolated directly from irradiated uranyl nitrate.