title: Measurement of accelerator bremsstrahlung spectra with a high-efficiency Ge detector.
abstract: A Compton spectrometer with a high-efficiency Ge detector was used to measure photon spectra from clinical accelerators. The response-function matrix for the detector system was determined using ten radioactive sources that emitted gamma rays of single energy ranging from 279-1525 keV. The system was tested by measuring the spectrum from a 60Co teletherapy machine. The energy distribution of tungsten target bremsstrahlung produced by 2.2, 2.5, 15, 20, and 25 MeV electrons in two clinical accelerators were determined. Theoretical thin-target calculations overestimate the number of photons in the high-energy regions of the spectra, as was expected. However, theoretical thick-target calculations underestimate the numbers of high-energy photons.
authors.affiliation: RADS, Inc., Lake Charles, Louisiana 70612.
authors.forename: D J
authors.initials: DJ
authors.lastname: Landry
authors.forename: D W
authors.initials: DW
authors.lastname: Anderson
mesh_terms: D005857:Germanium; D006801:Humans; D010315:Particle Accelerators; D011827:Radiation; D011874:Radiometry / Q000295:instrumentation*; D013057:Spectrum Analysis / Q000295:instrumentation*
chemical_list: D005857:Germanium