Characteristics of a radiation-charged electret dosimeter

Author

Fallone, B.G. ; MacDonald, B.A. ; Ryner, L.R.

Author_Institution

Dept. of Radiat. Oncology, McGill Univ., Montreal, Que., Canada

Volume

28

Issue

1

fYear

1993

fDate

2/1/1993 12:00:00 AM

Firstpage

143

Lastpage

148

Abstract

The radiation-charged electret ionization chamber uses an electret formed in situ by applying a bias voltage to the chamber electrodes while the chamber is being irradiated with X-rays. An electrometer permits measurement of the charge on the electret surface before and after the use of the chamber as a dosimeter. The authors present measurements of dosimeter range, sensitivity and energy dependence as functions of bias potential, electrode separation, guard ring size and various materials. Reproducibility permits detection as low as 80 μGy, with range to ~5 Gy, depending on the design of the chamber, with charge retention properties similar to electrets formed isothermally from corona discharge

Keywords

charge measurement; dosimeters; electrets; ionisation chambers; 8×10^-5 to 5 Gy; X-ray irradiation; bias potential; bias voltage; charge retention; corona discharge; dosimeter range; electrode separation; electrometer; energy dependence; guard ring size; ionization chamber; radiation-charged electret dosimeter; sensitivity; Charge measurement; Current measurement; Electrets; Electrodes; Energy measurement; Ionization chambers; Ionizing radiation; Size measurement; Voltage; X-rays;

fLanguage

English

Journal_Title

Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

0018-9367

Type

jour

DOI

10.1109/14.192251

Filename

192251