OPERATIONAL THERMOLUMINESCENE DOSIMETRY

by Claudio Furetta; Pao-Shan Weng; ; ;

• ISBN13: 9789810234683
• ISBN10: 9810234686
• Format: Nonspecific Binding
• Copyright: 1998-08-08
• Publisher: World Scientific Publishing

Summary

This book provides a comprehensive description of a dosimetric technique called thermoluminescence dosimetry. There are hundreds of scientific papers on thermoluminescence and its applications, but none deal with the "handling" of the technique, except for some official documents regarding procedural tests which are now not easily found. For this reason the authors have written this book with the aim of describing in detail how to use this dosimetric method. This volume is a valuable guide not only on the proper handling of the TL dozemeters but also on the results obtained by their use.The book consists of nine chapters. The first three chapters cover the theory of thermoluminescence and the experimental methods used to evaluate the kinetics parameters.The next three chapters describe the practical aspects of setting up a thermoluminescent dosimetric system, specifically suggesting the procedures to be used in handling the TL dosimeters as well as all the related instrumentation. The algorithm correlating the TL emission to the radiation dosage is provided and explained. The precision and accuracy of the TL measurements are also discussed.The last three chapters are devoted to: (i) the practical procedure used in some specific application fields, (ii) a discussion about the lower limit of detection and (iii) the TL instrumentation.Several practical illustrative examples are given throughout the text.The book is intended for students and researchers learning new techniques and those working in the area of radiation dosimetry with a specific interest in the TL technique.

Table of Contents

Theory of Thermoluminescence
Luminescence phenomena	1	(2)
Crystals and defects	3	(6)
Thermoluminescence	9	(2)
Mathematical treatment	11	(29)
Phosphorescence	13	(2)
A qualitative sketch	15	(2)
First order kinetics	17	(2)
Second order kinetics	19	(4)
Adirovitch theory	23	(4)
General order kinetics	27	(4)
Expressions with s independent on dose	31	(2)
Zero order kinetics	33	(1)
Mixed first and second order kinetics	34	(2)
Mean and half life	36	(3)
Interactive kinetics	39	(1)
On the frequency factor	40	(4)
Dependence of s, s' and s'' on temperature	44	(5)
First-order kinetics	44	(1)
Second-order kinetics	45	(1)
General-order kinetics	46	(3)
Experimental Methods to Evaluate the TL Parameters
Introduction	49	(1)
Methods based on the temperature at the maximum	49	(2)
Initial rise methods	51	(7)
Area measurement methods	58	(4)
Methods based on various heating rates	62	(5)
Isothermal decay method	67	(4)
Inflection points method	71	(5)
Numerical curve fitting methods	76	(3)
First-order kinetics	76	(1)
Second-order kinetics	77	(1)
General-order kinetics	78	(1)
Methods based on the analysis of the glow-curve shape	79	(7)
Keating method when s = s(T)	86	(3)
Moharil's methods	89	(9)
Christodoulides's method	98	(10)
Remarks on the Experimental Methods for Determining the Kinetics Parameters
General characteristics of first and second order glow-peaks	108	(1)
About the methods	109	(6)
About the heating rate	115	(6)
On the symmetry factor, m, and the order of kinetics, b	121	(6)
On the Set Up of a Thermoluminescent Dosimetric System
Introduction	127	(1)
Prerequisites	127	(1)
Initialisation procedure	128	(3)
Batch homogeneity	131	(4)
Reference and field dosimeters	135	(1)
Thermal treatments	136	(13)
General considerations	136	(6)
Annealing study	142	(7)
Dose Determination and Correlated Factors
Determination of the dose by thermoluminescence emission	149	(1)
Relative intrinsic sensitivity factor or individual correction factor Si	150	(11)
Calibration factor Fc	161	(3)
First procedure to obtain the calibration factor	162	(1)
Second procedure to obtain the calibration factor	163	(1)
Stability factor Fst	164	(2)
Procedure	164	(2)
Correction factor for the beam quality, Fen	166	(5)
Procedure for determining the energy dependence	169	(2)
Linearisation factor, Flin	171	(15)
General requirements for linearity	171	(3)
Experimental procedure	174	(2)
Non linearity	176	(6)
Methods for checking the linearity	182	(4)
Thermal fading	186	(5)
Procedure for thermal fading according a first order process	186	(2)
Self-dose in competition to fading	188	(3)
Precision and Accuracy
Introduction	191	(3)
Preliminary observations	191	(1)
Random uncertainties	192	(1)
Systematic uncertainties	193	(1)
Sources of error in thermoluminescent dosimetry	194	(3)
Sources of error due to the dosimeter	194	(2)
Errors generated in the reader	196	(1)
Errors due to the annealing procedures	197	(1)
Assessment of random uncertainties in precision of TL measurements	197	(12)
One single dosimeter undergoing repeated measurements	197	(1)
Several identical dosimeters submitted to one irradiation	198	(1)
Several identical dosimeters submitted to different doses	198	(3)
Several identical dosimeters undergoing repeated and equal irradiations	201	(8)
Accuracy of TL measurements	209	(3)
Practical Procedures in Some Application Fields
Introduction	212	(1)
Environmental monitoring	212	(6)
Optimization, calibration and measurement	213	(2)
Intercomparison	215	(1)
Evaluation of data	216	(1)
New approach to data analysis	217	(1)
Personal protection	218	(5)
Criteria for testing	218	(1)
Radiation sources	219	(1)
Phantom construction	220	(1)
Irradiation conditions	220	(1)
Others	221	(1)
Performance criterion	222	(1)
Accreditation	222	(1)
Steps in dose determination	223	(1)
Applications in medicine	223	(7)
Applications in diagnostic radiology	224	(1)
Applications in radiotherapy	224	(4)
Conclusion	228	(2)
Lower Limit of Detection
Introduction	230	(1)
Definitions	230	(4)
Theory	234	(7)
Levels of complexity	241	(3)
Concluding Remarks on a TL System
Introduction	244	(1)
Instrumentation	244	(3)
Set up of a TLD system	247	(1)
Procedure for checking the TLD system	248	(3)
Subject Index	251