A method for calculating the dose due to capture gamma rays in accelerator mazes.
An empirical technique for calculation of the capture gamma ray dose in the maze of high-energy medical accelerators is described. The total photon dose was measured along the maze centre line and by use of a graphical technique the capture gamma dose and the low-energy photon dose component were determined. Tenth-value lengths for both photon dose components are reported for four medical accelerators operating with megavoltages in the range 16.8-22.0 MV. The capture gamma dose and the low-energy photon dose in the maze were related to the following parameters: the room surface area, the distance from the isocentre to the inner maze entrance, and the neutron head leakage at a fixed distance from the target.
McGinley
P H
PH
Emory Clinic, Department of Radiation Oncology, Atlanta, GA 30322, USA.
Miner
M S
MS
Mitchum
M L
ML
D005720:Gamma Rays; D006801:Humans; D008433:Mathematics; D009502:Neutrons; D010315:Particle Accelerators; D017785:Photons; D011878:Radiotherapy / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage