Gamma Decay of the Lowly Excited States of ²²⁹AC

By bombarding the natural thorium targets with 14 MeVneutrons, ²²⁹Ra was produced through the reaction ²³²Th(n,α) ²²⁹Ra. The radium activities were separated from the irradiated targets by coprecipitation with BaC1₂. A total of 18 weak γ rays with energies of 14.5, 15.6, 18.8, 21.8, 22.5, 44.0, 47.5, 55.0, 63.0, 69.6, 93.6, 94.1, 98.5, 102.2, 104.5, 106.1, 161.1, and 171.5keV, which could be assigned to the decay of ²²⁹Ra, has been observed in the isolated radium fractions employing high-resolution HPGe detectors and γ (x)- γ coincidence methods. A decay scheme of ²²⁹Ra based on these observations has been proposed.