Radiative Electron Capture inFe55

The internal bremsstrahlung emitted in electron capture by ${\mathrm{Fe}}^{55}$ was studied from 14 kev to the upper energy limit at 220 kev. Fair agreement with the formula of Morrison and Schiff is observed at high energies, whereas a strong rise of the intensity occurs at low energies. The discrepancy may be due to failure of the theory to take into account the effects of nuclear charge, capture of $p$ electrons, and forbiddenness of the transition.