Measurement of Prepl Pwall factors in electron beams and in a 60Co beam for plane-parallel chambers.
This paper describes a method to measure the product of Prepl Pwall correction factors for ionization chambers and presents our measured values of Prepl Pwall for Markus plane-parallel chambers in electron beams. It is shown that the measured values of Prepl Pwall can be fitted to an equation, Prepl Pwall = c1 + c2 R50 + c3 (R50)2, for Markus chambers at the new reference depth for electron beams (6 MeV < or = nominal energy E < or = 20 MeV). We also present our measured values of Prepl Pwall for NACP and Markus chambers in a water phantom irradiated in a 60Co beam.
Ding
G X
GX
Fraser Valley Cancer Centre, British Columbia Cancer Agency, Surrey, Canada. gding@bccancer.bi.ca
Cygler
J E
JE
D002138:Calibration; D003037:Cobalt Radioisotopes / Q000627:therapeutic use*; D004583:Electrons; D008962:Models, Theoretical; D019047:Phantoms, Imaging; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D014867:Water
D003037:Cobalt Radioisotopes; D014867:Water