Internal and External Bremsstrahlung in Connection with the Beta Decay ofS35

The internal bremsstrahlung, emitted in the $\beta$ decay of ${\mathrm{S}}^{35}$, was investigated with a NaI scintillation spectrometer. Neither the shape of the spectral distribution nor the absolute yield was found to agree with theory. At 50 kev the experimental photon yield was 65 percent greater than the theoretical. At 100 kev it was even 180 percent greater. The total photon energy yield per $\beta$ decay, 2.23×${10}^{-5\mathrm{}}$ ${\mathit{mc}}^2$, was 35 percent greater than the calculated value.