AI Article Synopsis
- Free-air ionisation chambers are critical at standards laboratories for accurately measuring air kerma in X-ray fields.
- The diaphragm aperture size in these chambers is vital as it affects the X-ray beam size that interacts with the chamber.
- This study utilizes Monte Carlo simulation to determine correction factors for X-ray transmission and scatter affecting measurements of different-sized free-air ionisation chambers at various X-ray energies and distances.
Article Abstract
Free-air ionisation chambers are widely used at standards laboratories as primary standards for absolute measurements of air kerma in X-ray fields. The area of the diaphragm aperture of a free-air ionisation chambers is an important factor for absolute measurements because it defines the size of the X-ray beam incident on the free-air chamber. In this study, correction factors for the contribution of X rays transmitted through the diaphragm of a free-air ionisation chamber and those scattered from the surface of the diaphragm aperture are obtained by Monte Carlo simulation for two different sized free-air ionisation chambers and for various diaphragm aperture sizes, X-ray energies and source-to-chamber distances.
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| http://dx.doi.org/10.1093/rpd/ncr146 | DOI Listing |
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