Can anyone tell me how ADCL calibrate user's ion chambers?ADCL website explains the configuration in the following.
Please see the diagram in the website.http://rpc.mdanderson.org/adcl/absorbed.htm"
Absorbed Dose to WaterAbsorbed dose to water calibrations are performed in a 30 x 30 x 30cm3 phantom at 5 cm depth and 85 cm from the source. Water proofchambers are calibrated bare in water, other chambers are calibrated in1 mm PMMA water-proofing provided by the ADCL. The field size atthe location of the chamber is 10 x 10 cm2. The dose rate at thelocation of the chamber will be between 25 and 50 cGy/min."
I have a question here.TG-51 says that "The gradienteffects are included implicitly in the beam quality conversionfactor kQ for photons and explicitly by the term PgrQ for electrons."How the gradient effect is included for x-ray?I think it is something to do with how ADCL calibrate user's ionchamber.Can anyone explain?
Thanks,Jongmin
No comments:
Post a Comment