Radiations from Ba129
Abstract
The decay of Ba129 produced by an (n, 2n) reaction has been investigated. A new half-life value of 2.45+/-0.05 hours is reported. Gamma rays of 1.45, 0.210, 0.182, and 0.127 Mev with relative intensities 42, 65, 100, and ~26 were found, with coincidences between the 1.45-Mev and 0.182-Mev gammas. Milking experiments showed 25% to 30% of Ba129 to decay by β+ emission, based on assumptions about the unknown decay scheme of Cs129. This result is compatible with the intensities of K x-rays, positrons, and the various gamma rays only if unobserved γ-γ coincidence are postulated in addition to the reported ones. The result of the milking experiments is also in contradiction to the calculated Kβ+ ratio. 19% of the observed β+ transitions are in coincidence with the 0.210 and 5.6% with the 0.127-Mev gamma rays. Because of the mentioned discrepancies, no decay scheme can be proposed.
- Publication:
-
Physical Review
- Pub Date:
- February 1959
- DOI:
- 10.1103/PhysRev.113.863
- Bibcode:
- 1959PhRv..113..863H