Half-Lives of Radionuclides—IV

Half-lives of 61 radionuclides have been determined. In general, the activity of a purified sample was followed for two or more half-lives, but specific activities were used for some long-lived nuclides. Statistical methods, usually least-squares, were employed to obtain estimates of uncertainties. No significant differences in decay rates of ²⁴Na, ⁶⁴Cu, or ¹³¹I were found in various chemical states.