X-ray Spectrum from a Beryllium Window Tube: I. Scintillation Spectrometry

The X-ray beam from a commercial Be-window Machlett Type OEG-60 tube was analysed by a Nal(Tl) scintillation spectrometer. When the beam was filtered by inherent filtration plus ½ mil Al (the window of the detector), the count-rate spectrum showed an extra peak superimposed on the low-energy end of the bremsstrahlung continuum. Under the assumption of superimposition, area measurements gave a value of 30 per cent as the fractional contribution of this peak. This low-energy peak was attributed mainly to the tungsten L X rays from the target.