An ²²⁵Ac source was prepared and combined with a dedicated setup to collect recoil atoms which are ejected as a consequence of alpha decay. Some targets were made of acrylic glass and were then placed in custom-built triple-to-double coincidence ratio (TDCR) counters to measure the Cherenkov counting rates as a function of time. Half-lives of ²¹³Bi and ²⁰⁹Pb were derived from the data. In addition, polyethylene films were used as targets to collect recoil atoms. These films were then measured in a well-type NaI detector to detect gamma rays. The analysis of the data yielded an independent result for the half-life of ²¹³Bi. Combining the results of both measurement techniques, T_1/2(²¹³Bi) = (45.60 ± 0.09) min was obtained as a final value for the half-life of ²¹³Bi. The half-life of ²⁰⁹Pb was found to be T_1/2(²⁰⁹Pb) = (195.1 ± 2.6) min.

准备了一个²²⁵ Ac的离子源，并与专门的装置组合以收集反冲原子，这些原子由于α衰变而被喷射出去。一些目标是用丙烯酸玻璃制成的，然后放在定制的三重对偶重合率（TDCR）计数器中，以测量作为时间函数的Cherenkov计数率。从数据得出²¹³ Bi和²⁰⁹ Pb的半衰期。另外，聚乙烯薄膜被用作收集反冲原子的靶。然后在井式NaI检测器中测量这些膜以检测伽马射线。数据分析得出了²¹³ Bi半衰期的独立结果。结合两种测量技术的结果，T _1/2（^获得213 Bi）=（45.60±0.09）min，作为²¹³ Bi半衰期的最终值。发现²⁰⁹ Pb的半衰期为T _1/2（²⁰⁹ Pb）=（195.1±2.6）min。