Introduction Scintillator dosimeters (SD) have been a research topic by many groups over the last decade. The recent availability of a commercial system (Exradin W1 by Standard Imaging) represents a ...significant accomplishment. The attractiveness of SD would be furtherly enhanced by a scintillator free from any spectral superposition with the Cherenkov light, so to avoid any sensitive calibration procedure for the stem effect correction. Yb-doped silica optical fibres, thanks to their near-infrared (NIR) emission, proved to be a promising option. Purpose This study aims to characterize the dosimetric properties of Yb-doped fibers in radiotherapy and to compare their results with those obtained by various reference dosimeters like micro ion-chambers, the commercial SD, and diodes designed for small field dosimetry. Materials and methods Yb-doped fibres were prepared by sol–gel. The scintillation was detected with a laboratory-made photon counting system based on an avalanche photodiode (APD), using a long-pass filter at 950 nm. Irradiations were carried out with photons and electron beams generated by a Varian Trilogy accelerator. Results The NIR scintillation proved to be unaffected by the stem effect, even in unfavorable large field irradiations. The system showed a satisfactory reproducibility, good sensitivity, linear dose-rate response, independence of the signal (total counts) of dose rate and impinging beam orientation. The results were in good agreement with reference dosimeters in terms of relative dose profiles and output factors. Conclusion Findings pave the way to the engineering design of the system, which could be an interesting option also for real-time in-vivo dosimetry applications. Disclosure Authors declare no relationship that may bias the presentation.
FLARES (a Flexible scintillation Light Apparatus for Rare Event Searches) is a project for an innovative detector technology to be applied to rare event searches, and in particular to neutrinoless ...double beta decay experiments. Its novelty is the enhancement and optimization of the collection of the scintillation light emitted by ultra-pure crystals through the use of arrays of high performance silicon photodetectors cooled to 120 K. This would provide scintillation detectors with ~1% level energy resolution, with the advantages of a technology offering relatively simple low cost mass scalability and powerful background reduction handles, as requested by future neutrinoless double beta decay experimental programs.
Single crystals of PbWO
4 and Lu
3Al
5O
12-based scintillators were studied by correlated electron paramagnetic resonance and thermally stimulated luminescence experiments. The nature of some of the ...intrinsic trapping centers and their role in the energy transfer and storage processes were explained. Examples of material doping and co-doping are given, which succeeded in suppression of specific point defects and improvement of scintillation performance.
Thermally stimulated luminescence (TSL) properties of cerium and terbium doped SiO2 sol-gel glasses were studied after X-ray irradiation in the temperature range 10-700K. The role of Ce3+and Tb3+as ...recombination centers was shown. The existence of a distribution of trap levels was observed; the activation energies of such a distribution were calculated to extend from about 8x10-3eV up to 1DDT8eV for both cerium and terbium doped sol-gel glasses. The effect of a post-densification thermal treatment on TSL properties was also analyzed.
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