Radiative Electron Capture of ${\mathrm{Fe}}^{55}$, ${\mathrm{A}}^{37}$, and ${\mathrm{Ni}}^{59}$

The radiative electron capture spectra of ${\mathrm{Fe}}^{55}$, ${\mathrm{A}}^{37}$, and ${\mathrm{Ni}}^{59}$ were studied with a scintillation spectrometer. The end-point energies were found to be 226±10 kev, 815±20 kev, and 1065±30 kev, respectively. A method was devised to correct the experimental intensity distributions for distortions due to the Compton effect in the scintillation crystal. This was applied to the spectra of ${\mathrm{A}}^{37}$ and ${\mathrm{Ni}}^{59}$ above 320 kev. In this energy range, the experimental spectrum of ${\mathrm{A}}^{37}$ was found to agree with the calculated spectral shape. In the case of ${\mathrm{Ni}}^{59}$, a dependence of the spectral shape on the type of transition could not be detected within present experimental limits.