title: Measurement of backscatter to the monitor chamber of medical accelerators using target charge.
abstract: A simple noninvasive method is described for determining the backscatter to a monitor chamber of a medical accelerator based on the measurement of charge deposited in the target. This method is compared quantitatively to the more elaborate telescopic method for photon beams of 6 MV and 15 MV on linear accelerators having mica and Kapton monitor chambers. The new target charge method gives results consistent with the telescopic method to within 0.3%.
authors.affiliation: Department of Radiation Oncology, University of Michigan, Ann Arbor 48109-0010, USA.
authors.forename: K L
authors.initials: KL
authors.lastname: Lam
authors.forename: M S
authors.initials: MS
authors.lastname: Muthuswamy
authors.forename: R K
authors.initials: RK
authors.lastname: Ten Haken
mesh_terms: D004867:Equipment Design; D006801:Humans; D016018:Least-Squares Analysis; D010315:Particle Accelerators; D017785:Photons / Q000627:therapeutic use; D011880:Radiotherapy Planning, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D011882:Radiotherapy, High-Energy / Q000295:instrumentation / Q000379:methods*; D012542:Scattering, Radiation