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Updated: Aug 12, 2026

Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator
Published on: May 9, 2014
Dose rate outside primary barriers
1Emory Clinic, Department of Radiation Oncology, 1365 Clifton Road, Atlanta, GA 30322, USA. patton@radonc.emory.org
Abstract:
The author has investigated the use of the inverse square function to predict the photon dose rate outside primary barriers for medical accelerators. Measurements of the dose rate as a function of distance outside the barriers were made at five medical accelerator facilities. An analysis of the data showed that the radiation field appears to diverge from a point between the x-ray target and primary barrier. This behavior of the x-ray beam was attributed to scattering of photons in the shield barrier. It was concluded that the dose outside the barrier will be overestimated if the distance from the x-ray target to the point of calculation is utilized to carry out an inverse square correction.
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