Decay of Zr⁸⁶ and Gamma-Rays of Zr⁸⁷ and Zr⁸⁹

Abstract

The decay of Zr⁸⁶ has been studied with scintillation techniques and a magnetic beta-spectrometer. Besides the previously reported (247±2) keV gamma-ray, new (615±5) and (32±3) keV gamma-rays have been found. The relative intensities of the 32, 247 and 615 keV gamma-rays are ∼25, 100 and 7±2, respectively, The K⁄(L+M) ratio and K conversion coefficient of the 247 keV transition are (6.1±0.3) and (1.4±1.5)×10⁻², respectively. The half-life of Zr⁸⁶ has been determined as (16.5±0.1) h. The decay scheme of Zr⁸⁶ is discussed on the basis of these results. A new (2.2±0.1) MeV gamma-ray of Zr⁸⁷ has been found and the (1.2±0.05) MeV gamma-ray of Zr⁸⁷ and the (1.7±0.1) MeV gamma-ray of Zr⁸⁶ has been confirmed.