Detector cintilador semicondutor para radiação gama

Abstract

Nowadays the devices employed to evaluate individual radiation exposition are based on dosimetric films and ter-moluminescent crystals, whose measurements must be processed in specific transductors. Hence, these devices carry out indirect measurements. Although a new generation of detectors based on semiconductors which are employed in EPD’s (Eletronic Personal Dosimeters) being yet available, it high producing costs and large dimensions prevents the application in personal dosimetry. Recent research works reports the development of new detection devices based on photovoltaic PIN diodes, which were succesfully employed for detecting and monitoring exposition to X rays. In this work, we step forward by coupling a 2mm antracene scintillator NE1, which converts the high energy radiation in visible light, generating a Strong signal which allows dispensing the use of photomultipliers. A low gain high performance amplifier and a digital acquisition device are employed to measure instantaneous and cum-mulative dosis for energies ranging from X rays to Gamma radiation up to 2 MeV. One of the most important fea-tures of the PIN diode relies in the fact that it can be employed as a detector for ionization radiation, since it requires a small energy amount for releasing electrons. Since the photodiode does not amplify the corresponding photon current, it must be coupled to a low gain amplifier. Therefore, the new sensor works as a scintillator coupled with a photodiode PIN. Preliminary experiments are being performed with this sensor, showing good results for a wide range of energy spectrum.