Spins und γ-Multipolordnungen beim Zerfall Fe⁵⁹→Co⁵⁹

Abstract

In the decay of Fe⁵⁹ the following quantities have been measured:γ-ray intensities, conversion coefficients andβ-(circularly polarizedγ) correlations. The conversion coefficients were found to be: for the 1.10 MeVγ-transition, α_tot.=(1.36±0.10)·10⁻⁴ and for the 1.29 MeVγ-transition, α_tot.=(1.07±0.08)·10⁻⁴. The asymmetry parameterA of the correlationβ(0.27 MeV)−γ(1.29 MeV) were measured to beA= −0.17±0.10, and forβ(0.46 MeV)−γ(1.10 MeV),A=−0.13±0.04. From these data and publishedγ−γ angular correlation measurements the following spins of Co⁵⁹ levels could be deduced: 1.10 MeV,I=5/2⁻; 1.29 MeV,I=5/2⁻; and 1.43 MeV,I=3/2⁻. The two strongβ-ray groups are pure Gamow-Teller transitions (ΔI=1). The multipolarities of all fiveγ-rays are given.