Energy Spectra of Electrons Emerging from Lead Exposed to 320 kVp White X-rays

Abstract

The energy spectra of secondary electrons, which emerge perpendicularly from a lead-foil exposed to 320 kVp therapeutic white x-rays (HVL=3 mmCu), are observed by a double-focusing magnetic beta-spectrometer. For the foil thicknesses 0.4–34 mg/cm2 and the x-ray incident angles less than 80°, the emerging electrons are found in the energy region less than 220keV with the maximum counts at 50–80 keV (mean energy: 75–100 keV). For a given foil thickness, the spectral shape is almost independent of the incident angle of x-rays. With the increase in foil thicknesses, however, the high-energy part of the spectra is markedly intensified.