National Physical Laboratory

Secondary electron perturbations in Farmer type ion chambers for clinical proton beams

Further Information

Published: 19 November 2010

Author: Hugo Palmans

Related: Radiation Dosimetry  

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IAEA TRS-398, ICRU Report 78 and earlier recommendations assume that ion chamber perturbation factors in proton beams are unity for all ionisation chamber types. Some experimental and Monte Carlo studies have indicated that wall and central electrode perturbation corrections are not negligible.

Here, calculations of the wall and central electrode perturbation correction factors, pwall and pcel, are presented for Farmer type chambers using egsnrc.


Last Updated: 26 Mar 2014
Created: 28 Oct 2011


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