Internal Conversion inNi60

Abstract

The coefficients of internal conversion for the two gamma-rays accompanying the decay of ${\mathrm{Co}}^{60}$ have been measured. For the 1.17-Mev gamma-ray we find $\alpha =2.3\mathrm{}\times {10}^{-4\mathrm{}}$, for the 1.33-Mev ray $\alpha =1.8\mathrm{}\times {10}^{-4\mathrm{}}$. Comparison with theoretical values indicates that the parity change must be the same in both transitions and that the two gamma-rays are probably electric quadrupoles.