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Thermoluminescence (TL) and optically stimulated luminescence (OSL) are two of the most important techniques used in radiation dosimetry. They have extensive practical applications in the monitoring of personnel radiation exposure, in medical dosimetry, environmental dosimetry, spacecraft, nuclear reactors, food irradiation etc., and in geological /archaeological dating. Thermally and Optically Stimulated Luminescence: A Simulation Approach describes these phenomena, the relevant theoretical models and their prediction, using both approximations and numerical simulation. The authors concentrate on an alternative approach in which they simulate various experimental situations by numerically solving the relevant coupled differential equations for chosen sets of parameters. Opening with a historical overview and background theory, other chapters cover experimental measurements, dose dependence, dating procedures, trapping parameters, applications, radiophotoluminescence, and effects of ionization density. Designed for practitioners, researchers and graduate students in the field of radiation dosimetry, Thermally and Optically Stimulated Luminescence provides an essential synthesis of the major developments in modeling and numerical simulations of thermally and optically stimulated processes.

Optically stimulated luminescence has developed into one of the leading optical techniques for the measurement and detection of ionizing radiation. This text covers, in a readable manner, advanced modern applications of the technique, how it can play a useful role in different areas of dosimetry and how to approach the challenges presented when working with optically stimulated luminescence. The six chapters are as follows: * Introduction, including a short history of OSL and details of successful applications * Theory and Practical Aspects * Personal Dosimetry * Space Dosimetry * Medical Dosimetry * Other Applications and Concepts, including retrospective and accident dosimetry, environmental monitoring and UV dosimetry Throughout the book, the underlying theory is discussed on an as-needed basis for a complete understanding of the phenomena, but with an emphasis of the practical applications of the technique. The authors also give background information and relevant key references on each method, inviting the reader to explore deeper into the subject independently. Postgraduates, researchers, and those involved with radiation dosimetry will find this book particularly useful. The material is both relevant and accessible for both specialists and those new to the field, therefore is fundamental to any academic interested in modern advances of the subject.

The purpose of this study was to evaluate scatter radiation dose to the subject surface during X-ray computed tomography (CT) fluoroscopy using the integrated dose ratio (IDR) of an X-ray dose profile derived from an optically stimulated luminescent (OSL) dosimeter. We aimed to obtain quantitative evidence supporting the radiation protection methods used during previous CT fluoroscopy. A multislice CT scanner was used to perform this study. OSL dosimeters were placed on the top and the lateral side of the chest phantom so that the longitudinal direction of dosimeters was parallel to the orthogonal axis-to-slice plane for measurement of dose profiles in CT fluoroscopy. Measurement of fluoroscopic conditions was performed at 120 kVp and 80 kVp. Scatter radiation dose was evaluated by calculating the integrated dose determined by OSL dosimetry. The overall percent difference of the integrated doses between OSL dosimeters and ionization chamber was 5.92%. The ratio of the integrated dose of a 100-mm length area to its tails (-50 to -6 mm, 50 to 6 mm) was the lowest on the lateral side at 80 kVp and the highest on the top at 120 kVp. The IDRs for different measurement positions were larger at 120 kVp than at 80 kVp. Similarly, the IDRs for the tube voltage between the primary X-ray beam and scatter radiation was larger on the lateral side than on the top of the phantom. IDR evaluation suggested that the scatter radiation dose has a high dependence on the position and a low dependence on tube voltage relative to the primary X-ray beam for constant dose rate fluoroscopic conditions. These results provided quantitative evidence supporting the radiation protection methods used during CT fluoroscopy in previous studies.

This article investigates the performance of a commercial BeO optically stimulated luminescent (OSL) dosimetry system (myOSLchip, RadPro GmbH International, Remscheid, Germany) through the application of the commissioning framework for luminescent dosimeters as described in the American Association of Physicists in Medicine Task Group 191 (AAPM TG191) report. Initial clinical experiences and dosimetric results are also presented. The following properties of the system were characterized: linearity correction factors ranged from ‐0.5% to +3% for dose levels spanning 0.1 to 20 Gy. Beam quality correction factors (relative to 6 MV) ranged from ‐4.5% (2.5FFF) to +4.5% (15MV) for photon beams and +1.9% (6 MeV) to +4.3% (20 MeV) for electron beams. An average (µ) signal loss per reading of ‐2.13% ± 0.20% was measured, however greater signal loss was observed in the first reading (µ = ‐2.6% ± 0.46%). An initial decline in individual element sensitivity relative to baseline was observed from 0–15 Gy cumulative dose (µ = ‐1.98% ± 0.55%), with negligible further deterioration from 15–32 Gy (µ = ‐2.38% ± 0.85%). Post‐irradiation, there was a transient OSL signal which faded with a half‐life of 1.8 min; this signal enhancement was +5% at 5 min post‐irradiation and +1% at 15 min relative to 24 h. Dosimeter response was not dependent on average dose rate in the range of 100–2500 MU/min. With respect to clinical testing, equal or superior performance compared with aluminum oxide OSLs (nanoDots) is shown for a range of clinical techniques and modalities including TSET, TBI, en‐face electrons, and pacemaker/out‐of‐field measurements. The feasibility of myOSLchip to serve as a primary clinical in vivo dosimetry system and direct replacement for Landauer's microStar system is demonstrated.

In radiation oncology, inter‐fractional dosimetry using optically stimulated luminescent detectors (OSLDs) ensures accurate plan delivery and patient safety. RadPro International GmbH's myOLSchip system, featuring a beryllium oxide (BeO) OSL dosimeter, reader, and eraser, was characterized and calibrated with a Varian Truebeam for in‐vivo dosimetry following AAPM TG‐191 guidelines. The BeO detectors demonstrated good dose linearity and repeatability across multiple exposures and erasure cycles, aligning with the manufacturer's stated accuracy and precision.

Aim: The aim of this study was to carried out the audit of radiotherapy centers practicing conformal radiotherapy techniques and demonstrate the suitability of this indigenous optically stimulated luminescence (OSL) disc dosimeters in beam quality audit and verification of patient-specific dosimetry in conventional and conformal treatments in radiotherapy. Materials and Methods: Dose audit in conventional and conformal (intensity-modulated radiotherapy and volumetric-modulated arc therapy) radiotherapy techniques was conducted using in-house developed Al2O3:C-based OSL disc dosimeter and commercially available Gafchromic EBT3 film in 6 MV (flat and unflat) photon and 6 and 15 MeV electron beams. OSL disc dosimeter and Gafchromic EBT3 film measured dose values were verified using the ionization chamber measurements. Results: Percentage variations of doses measured by OSL disc dosimeters and EBT3 Gafchromic film for conventional radiotherapy technique were in the range of 0.15%-4.6% and 0.40%-5.45%, respectively, with respect to the treatment planning system calculated dose values. For conformal radiotherapy techniques, the percentage variations of OSL disc and EBT3 film measured doses were in the range of 0.1%-4.9% and 0.3%-5.0%, respectively. Conclusion: The results of this study supported by statistical evidence provided the confidence that indigenously developed Al2O3:C-based OSL disc dosimeters are suitable for dose audit in conventional and advanced radiotherapy techniques.

We aimed to evaluate properties of optically stimulated luminescence dosimeters (OSLDs) and radiophotoluminescent glass dosimeters (RPLDs) used in dual-source dual-energy (DE) computed tomography (DECT) dosimetry. Energy dependence was evaluated in single-energy (SE) and DE modes, and their relative dose responses differed by 3.8% and 6.6% under equivalent effective energy with OSLD and RPLD, respectively. Dose variation was evaluated using coefficients of variation of dose values from 10 dosimeters, and dose variation of OSLD and RPLD in SE mode ranged from 2.1 to 3.0% and from 2.1 to 2.8%, and those in the DE mode were 1.8 and 2.6%, respectively. Dose linearity was evaluated from 1 to 150 mGy, and linear relationships of dose response were observed between the dosimeters and the ionization chamber (correlation coefficients ≥ 0.9991). Angular dependence was evaluated from − 90° to + 90°, and it was smaller in DE mode than in SE mode for OSLD. The normalized response of RPLD was higher at ± 30° and ± 60° and lower at − 90° in SE and DE modes. This study demonstrated both OSLD and RPLD can perform dosimetry in dual-source DECT with small influence of the properties of the dosimeters compared with that in SECT.

This study aimed to evaluate the property of small dosimeters used for measuring eye lens doses for medical staff during fluoroscopic examination. Dose linearity, energy dependence, and directional dependence of scattered X-rays were evaluated for small radiophotoluminescence glass dosimeters (RPLDs), those with a tin filter (Sn-RPLDs), and small optically stimulated luminescence dosimeters (OSLDs). These dosimeters were pasted on radioprotective glasses, and accumulated air kerma was obtained after irradiating the X-rays to a patient phantom. Strong correlations existed between fluoroscopic time and accumulated air kerma in all types of dosimeters. The energy dependence of Sn-RPLD and OSLD was smaller than that of RPLD. The relative dose value of the OSLD gradually decreased as the angle of the OSLD against the scattered X-rays was larger or lower than the right angle in the horizontal direction. The ranges of relative dose values of RPLD and Sn-RPLD were larger than that of OSLD in the vertical direction. The OSLDs showed lower doses than the RPLDs and Sn-RPLDs, especially on the right side of the radioprotective glasses. These results showed that RPLDs, Sn-RPLDs, and OSLDs had different dosimeter properties, and influence measured eye lens doses for the physician, especially on the opposite side of the patient.

The modern radiotherapy techniques impose new challenges for dosimetry systems with high precision and accuracy in in vivo and in phantom dosimetric measurements. The knowledge of the basic characterization of a dosimetric system before patient dose verification is crucial. This incites the investigation of the potential use of nanoDot optically stimulated luminescence dosimeter (OSLD) for application in radiotherapy with therapeutic photon beams. Measurements were carried out with nanoDot OSLDs to evaluate the dosimetric characteristics such as dose linearity, dependency on field size, dose rate, energy and source-to-surface distance (SSD), reproducibility, fading effect, reader stability, and signal depletion per read out with cobalt-60 (60 Co) beam, 6 and 18 MV therapeutic photon beams. The data acquired with OSLDs were validated with ionization chamber data where applicable. Good dose linearity was observed for doses up to 300 cGy and above which supralinear behavior. The standard uncertainty with field size observed was 1.10% ± 0.4%, 1.09% ± 0.34%, and 1.2% ± 0.26% for 6 MV, 18 MV, and 60 Co beam, respectively. The maximum difference with dose rate was 1.3% ± 0.4% for 6 MV and 1.4% ± 0.4% for 18 MV photon beams. The largest variation in SSD was 1.5% ± 1.2% for 60 Co, 1.5% ± 0.9% for 6 MV, and 1.5% ± 1.3% for 18 MV photon beams. The energy dependence of OSL response at 18 MV and 60 Co with 6 MV beam was 1.5% ± 0.7% and 1.7% ± 0.6%, respectively. In addition, good reproducibility, stability after the decay of transient signal, and predictable fading were observed. The results obtained in this study indicate the efficacy and suitability of nanoDot OSLD for dosimetric measurements in clinical radiotherapy.

We describe an elephant skull recovered from a cliff section of Dhasan river of Marginal Ganga Plain. The dental morphology and cranial features of the skull have been compared with the known species of Elephas from the Indian subcontinent. Although it shows very near resemblance to Elephas namadicus, but being an isolated specimen its specific identity cannot be proclaimed with certainty. As such, the specimen is provisionally referred as E. cf. namadicus. The Optically Stimulated Luminescence ages place this find at ≈56 ka BP. This is the first chronologically well constrained report of E. cf. namadicus from the Ganga Plain. Copyright 2016 Geological Society of India