In the nineteen years, 1965-1983, spanning the seven international conferences devoted to luminescence dosimetry, the applications of thermoluminescence to ionizing radiation dosimetry have become legion. There is no doubt that thermoluminescence now occupies a central and constantly expanding role in ionizing radiation dosimetry in the fields of clinical radiation therapy and diagnostics as well as personnel radiation protection and environmental radiation dosimetry.
The commercial development of an extended variety of solid TL dosimeters (TLDs}, hot pressed and extruded ribbons, chips and rods, throw-away capsules, and teflon® discs, which can routinely yield 3% precision of measurement, have greatly influenced the acceptance of TLDs in the clinical environment. Loose powders have also remained in use due to the convenience of being able to adjust the dosimeter mass, the slightly higher precision (1 to
2%), and the ability to vary the shape of the dosimeter for specific applications. National and international quality assurance programs using TLDs sent by post are also have an increasingly significant role in establishing widespread confidence in the techniques of TL dosimetry. In addition, working groups have been established for the preparation of inter• national standards for TLDs and TL readers. Reliable TL readers of various levels of sophistication are commercially available, and even the relatively lower priced systems have been found adequate for many routine clinical applications. A parallel development has been the gradually accelerating acceptance of TL dosimetry in the fields of personnel radiation protection and environmental dosimetry. TL dosimetry naturally lends itself to automation and the less stringent requirements for precision are easily fulfilled by TLDs in many radiation environments. A decade of intensive experimental investigation has mapped out the TL properties of many materials and their interaction with various types of radiation fields. Continuing investigations will certainly bring further significant developments. A greater understanding of the difficulties associated with TL dosimetry has also emerged. The TL properties of a particular material are dependent not only on the incorporation of ppm impurities, but also on other defects incorporated into the starting material, or during the material preparation, or by the radiation and thermal treatments applied to the TLD. Thus two materials of nominally identical doping, and even purchased from the same source, may show annoyingly different TL properties. This situation is particularly expressed in the ionization density dependence of the TL efficiency. The nonuniversality of many other important TL properties has led, in certain cases, to significant difficulties of interpretation. For example, it is still not clear to what extent the "over-response" of TLDs to low energy X-rays and the "under-response" to high energy electrons and X-rays are dependent on material composition. Even relative TL properties may also depend on an impressive number of experimental factors. Although several books have been written on TL dosimetry these have been somewhat introductory in nature and too brief to really present to the reader the full complexity of the subject. These volumes are intended to fill the gap both in the depth and breadth of treatment and have thus been primarily written as a reference work for radiation and nuclear scientists and dosimetrists and solid state physicists interested in radiation dosimetry. To this end, effort has been made to include many useful tables, illustrations, and formulas and a comprehensive list of references to the literature is also included following each chapter. Every effort, however, has been made to present the material as logically as possible and with adherence to basic physical principles so that these volumes should also prove useful for TL dosimetrists and scientists just entering the field. Each chapter, covering an important aspect of TL or its application to dosimetry, is written in sufficient detail to give the reader a complete grasp of the subject; the approach is often critical as in the nature of a review article so as to highlight current problems in the field.
The first volume (four chapters) deals with the basic physical and scientific aspects of
TL so often essential to optimum use of TL in radiation dosimetry

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