Direct Determination of Internal Conversion Coefficients

Using the same source and instrument geometry, both the external as well as internal conversion lines of the 1.17- and 1.33-Mev gamma rays of ${\mathrm{Co}}^{60}$ are scanned in a Siegbahn-Slätis spectrometer. From the known internal conversion coefficients of these gamma rays, the instrument is calibrated for the direct determination of internal conversion coefficient of any other gamma rays having energy near 1.3 Mev. As an example, the internal conversion coefficient of the 1.408-Mev gamma ray, in the decay of ${\mathrm{Eu}}^{152}$, is measured. The value obtained is 4.99×${10}^{-4\mathrm{}}$.