BETA-GAMMA (CP) CORRELATION AND GAMMA SPECTROSCOPY IN 27MG

The β-decay of 27Mg has been studied by Ge(Li) γ-ray spectroscopy and by β-γ (CP) correlation measurements. The spectroscopy work gave the following γ-ray energies (and intensities): 170.82±0.10 keV (0.85±0.04 %), 843.76±0.10 keV (72.1±0.9%), 1014.52±0.10 keV (27.0±0.4 %). These intensities lead to (β-branching ratios of 72.1±0.4% and 27.9±0.4% through the 1015 keV and the 844 keV states, respectively, and also yield the γ-branching of 3.05 0 ̄.15 % from the 1015 keV level through the 844 keV level. Using a transmission polarimeter, the asymmetry parameterA = -0.103±0.040 for the 1 2+β→ 3 2+γ→ 5 2+ decay was obtained. This leads to the value 〈E2〉/〈M1〉 = -0.322±0.034 for the 1015 keV γ-ray. This transmission datum in conjunction with that obtained using a scattering polarimeter gave A = -0.221±0.019 for the 1 2+β→ 3 2+γ→ 5 2+ decay. This yields Cv〈Mv〉/CA〈MA〉 = 0.007±0.046 for the 844 keV γ-ray, which corresponds to a Coulomb matrix element of 9±53 keV between the analog of the 27Mg ground state and the 844 keV state of Al. © 1969.