This paper presents the results obtained in a study of LiF TLD-100 performance for mailed dosimetry in radiotherapy, using glow curve analysis of TL evaluation and reusable chips. An excellent reusability is assured by a simple thermal treatment of 1 h at 400 degrees C followed by a controlled and reproducible cooling to room temperature that accurately reproduces the sensitivity of the detectors. Particular attention was devoted to studying sensitivity changes during room temperature storage of TLD-100 detectors. These changes can be one of the major sources of uncertainty in mailed dosimetry, where long intervals can occur between detector preparation, irradiation and readout. Based on the features of the individual peak evolution during storage a rather simple method to correct for these sensitivity modifications is proposed. The analysis of the different influential factors permitted us to estimate a combined uncertainty for the measurement of absorbed doses within the 0.5-4 Gy range of 1.0%.

New experimental results are presented concerning the isothermal decay associated with peaks IV and V in TLD-100. The identification of the individual contributions of these glow peaks to the TL decay, together with the detailed study of the features of the glow curves and the isothermal decays obtained following well specified annealing treatments, permits a coherent and complete interpretation of this controversial decay, suggesting the existence of a new, low-intensity, glow peak situated between peaks IV and V.

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Presents some additional evidence against the recent identification of peak IV in the TL and PTTL glow curves of heavily annealed TLD-100. Deconvolution analysis of the glow curves, produced by annealing for progressively increasing durations at 150 degrees C, permits the identification of a new and relatively broad peak, centered at 162 degrees C. This should not be confused with peak IV (182 degrees C), despite their relative proximity in temperature.

Within the scope of CONRAD (A Coordinated Action for Radiation Dosimetry) Work Package 4 on Computational Dosimetry jointly collaborated with the other research actions on internal dosimetry, complex mixed radiation fields at workplaces and medical staff dosimetry. Besides these collaborative actions, WP4 promoted an international comparison on eight problems with their associated experimental data. A first set of three problems, the results of which are herewith summarised, dealt only with the expression of the stochastic uncertainties of the results: the analysis of the response function of a proton recoil telescope detector, the study of a Bonner sphere neutron spectrometer and the analysis of the neutron spectrum and dosimetric quantity H(p)(10) in a thermal neutron facility operated by IRSN Cadarache (the SIGMA facility). A second paper will summarise the results of the other five problems which dealt with the full uncertainty budget estimate. A third paper will present the results of a comparison on in vivo measurements of the (241)Am bone-seeker nuclide distributed in the knee. All the detailed papers will be presented in the WP4 Final Workshop Proceedings.

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This paper presents results obtained in a detailed study of the changes induced in TLD-1 00 glow peaks IV and V, during storage at 45 'C for up to 10 days.The modifications exhibited by the glow curve have been studied using a computer fitting programme to resolve the individual peak components. While peak V only experiences an increase in the number of traps, peak IV suffers marked modifications in position, intensity and width, revealing important changes in the trap structure, affecting to a different extent empty or filled traps. No evidence for loss of TL signal due to leakage of trapped charges has been found for peaks IV and V, during storage at 45 "C.

Isothermal decay (ID) experimental data for peaks 2, 3 and 4 of LiF:Mg,Cu,P (China) are presented. For every peak the ID has been measured at different temperatures, so that the evolution of life-time with temperature has also been determined. Peaks 2 and 4 present a very simple exponential decay typical of first order kinetic processes. Peak 3 decay is more complex due to the unavoidable contribution of the intense peak 4. After the subtraction of this contribution, peak 3 decay is exponential indicating first order kinetics for this peak too. From the good linear dependence of lnt on l/T, values for the activation energy and the frequency factor for all the peaks studied have been obtained. Peak 4 parameters have shown to be very critically dependent on the cooling rate in the annealing procedure. The LiF:Mg,Cu,P decay features are discussed with regard to those of LiF:Ti,Mg (TLD-100).