Fibre remote optoelectronic gamma dosimetry based on optically stimulated luminescence of Al2O3:C

Optically stimulated luminescence dosimetry (OSL-D) used in conjunction with fibre optics enables a remote measurement of dose, for the purpose of radioprotection in the nuclear industry and in medicine (radiology, radiotherapy). Alumina OSL crystals are used because of their low Z, low fading and optical transparency, which improves the sensitivity. An optoelectronic portable dosemeter has been designed and tested that shows a dose detection of 50 microGy with a 20 metre-long fibre. Following irradiation, all trapped electrons are released under light stimulation while the OSL is integrated to provide dose-equivalent measurements. A compensation technique is designed with the help of the MCNP4b code, so that both angular and photon energy characteristics comply with international standards (CEI 61066) for photon dose equivalent Hp(10). Two sensors are described that allow measurements over a wide solid angle (95% of 4piSr), for photon energies ranging from 15 keV to 3 MeV.