Energies of the Radiations fromCo57andCo58

Using magnetic and scintillation spectrometers the energies of the radiations from ${\mathrm{Co}}^{57}$ and ${\mathrm{Co}}^{58}$ have been evaluated. Several gamma rays not previously reported have been observed. ${\mathrm{Co}}^{57}$ decays mainly by $K$ capture but also to a slight extent by positron emission with an upper energy limit of about 300 kev, followed by gamma rays with energies 14.6, 29, 99.8, 122.8, 137.4, and 700 kev. ${\mathrm{Co}}^{58}$ decays by $K$ capture and with positron emission of upper energy 485±10 kev. Gamma rays with energies of 814 and 500 and possibly 1300 kev accompany the decay.