You need JavaScript to view this

Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors

Abstract

The thesis presents criteria for thermoluminescence dosimetry systems suitable for precision measurements and, moreover, a detailed examination of the sources of systematic and random error. Instructions are given for annealing processes, calibration procedures, quality control, and operational rules, which are necessary in modem TLD. The performances of some principally different systems are compared. The old LiF-powder-based TLD system, with an overall uncertainty of measurement of about 1.6 percent for ten repeated readouts and for irradiations under calibration conditions with Co-60, is still the best but a comparable, although slightly lower, accuracy of about 1.7 percent can be reached more conveniently with solid LiF detectors. In measurements where absolute system calibration is not of interest (i.e., in depth-dose curve measurements, etc.), the advantages of the simple powder-based system are even more concrete. An integrated TLD process is presented for progressive utilization of automation in precision measurements. The sources of random error and unknown systematic error in current readout instruments are examined. Mechanical tolerances in critical parts of the readout instruments are thought to be the reason why the method of heating with hot gas has not been superior with respect to the precision of measurements, in spite of the excellent repeatability  More>>
Authors:
Publication Date:
Aug 01, 1991
Product Type:
Thesis/Dissertation
Report Number:
STUK-A-101
Reference Number:
SCA: 440102; PA: AIX-24:002603; SN: 93000913327
Resource Relation:
Other Information: DN: The thesis also includes six previosly published articles.; TH: Thesis (Ph.D.).; PBD: Aug 1991
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; THERMOLUMINESCENT DOSIMETRY; ANNEALING; LITHIUM FLUORIDES; QUALITY CONTROL; SENSITIVITY; THERMOLUMINESCENT DOSEMETERS; 440102; RADIATION DOSEMETERS
OSTI ID:
10108865
Research Organizations:
Finnish Centre for Radiation and Nuclear Safety (STUK), Helsinki (Finland)
Country of Origin:
Finland
Language:
English
Other Identifying Numbers:
Other: ON: DE93609497; ISBN 951-47-5338-0; TRN: FI9200087002603
Availability:
OSTI; NTIS; INIS
Submitting Site:
FIN
Size:
[72] p.
Announcement Date:
Jun 30, 2005

Citation Formats

Toivonen, M. Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors. Finland: N. p., 1991. Web.
Toivonen, M. Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors. Finland.
Toivonen, M. 1991. "Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors." Finland.
@misc{etde_10108865,
title = {Improved processes in therapy dosimetry with solid LiF thermoluminescent detectors}
author = {Toivonen, M}
abstractNote = {The thesis presents criteria for thermoluminescence dosimetry systems suitable for precision measurements and, moreover, a detailed examination of the sources of systematic and random error. Instructions are given for annealing processes, calibration procedures, quality control, and operational rules, which are necessary in modem TLD. The performances of some principally different systems are compared. The old LiF-powder-based TLD system, with an overall uncertainty of measurement of about 1.6 percent for ten repeated readouts and for irradiations under calibration conditions with Co-60, is still the best but a comparable, although slightly lower, accuracy of about 1.7 percent can be reached more conveniently with solid LiF detectors. In measurements where absolute system calibration is not of interest (i.e., in depth-dose curve measurements, etc.), the advantages of the simple powder-based system are even more concrete. An integrated TLD process is presented for progressive utilization of automation in precision measurements. The sources of random error and unknown systematic error in current readout instruments are examined. Mechanical tolerances in critical parts of the readout instruments are thought to be the reason why the method of heating with hot gas has not been superior with respect to the precision of measurements, in spite of the excellent repeatability of the glow curve shape observed for successive readouts.}
place = {Finland}
year = {1991}
month = {Aug}
}