[Practical electron dosimetry. A comparison of different types of ionization chambers]

Z Med Phys. 2002;12(1):24-8. doi: 10.1016/s0939-3889(15)70540-4.
[Article in German]

Abstract

Since Markus chambers are no longer recommended in the 1997 DIN 6800-2 version there are uncertainties as to the use of alternative chamber types for electron dosimetry. Therefore, we performed a comparison between different types of ionization chambers. In particular, the widespread Farmer and Roos chambers were compared with the Markus chamber for polarity effect, chamber-to-chamber variation, and deviations of the measured absorbed dose relative to the value obtained with the Roos chamber (which is regarded as an ideal Bragg-Gray-chamber). The perturbation correction factor at 60Co radiation was determined experimentally as 1,029 +/- 0.5% (Roos chamber) and 1,018 +/- 0.5% (Markus chamber) for the investigated plane-parallel chambers. In addition, we could show that the Roos chambers do not have a larger chamber-to-chamber variation than the Farmer chambers. Likewise, our results suggest that Farmer chambers could be used for electron energies above 6 MeV.

Publication types

  • Comparative Study
  • English Abstract

MeSH terms

  • Electrons
  • Protons*
  • Radiometry / instrumentation
  • Radiometry / methods

Substances

  • Protons