title: Comparison of dose calibration by ionometric and chemical dosimetry for 6- and 45-MV x-ray beams.
abstract: This work reports the results of an experiment carried out to investigate the compatibility of TG-21 ion chamber calibration with Fricke dosimetry near the extremes of the clinically available megavoltage photon energy range. Doses determined from ion chamber measurements and from chemical dosimetry are compared for a 6-MV linear accelerator x-ray beam and 45-MV betatron beam. The Fricke dosimetry was carried out by the National Institute of Standards and Technology. Agreement within 1% between the two techniques was obtained at both photon energies using a currently accepted G-value.
authors.affiliation: Medical College of Virginia, Richmond 23298.
authors.forename: R D
authors.initials: RD
authors.lastname: Zwicker
authors.forename: A
authors.initials: A
authors.lastname: Wu
authors.forename: E S
authors.initials: ES
authors.lastname: Sternick
mesh_terms: D002138:Calibration; D006801:Humans; D011874:Radiometry / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage / Q000592:standards*; D011882:Radiotherapy, High-Energy / Q000592:standards*