Spectroscopy of the gamma and X ray leakage radiation from the built-in sources of a Risø TL/OSL reader

• We measured the leakage spectra from the built-in radiation sources in a Risø TL/OSL reader.
• Leakage spectrum under the beta source corresponds to a Bremsstrahlung X-ray emission with characteristic lines from Pb and Bi.
• TL and OSL detectors were used in order to determine the air dose rates due to the leakage radiation.
• Dose rates ranging from 50 to 100 μGy h−1 were obtained under the beta and alpha sources.

In this work we evaluate the intensity and the spectral shape of the leakage radiation from the built-in beta and alpha sources of a Risø TL/OSL reader. LiF (TLD-100), fluorite-based pellets and Al2O3:C detectors were used in order to determine the dose rate delivered to the dosimeters when the sources are closed. The leakage spectra under both alpha and beta sources were registered with a CdTe semiconductor detector. The spectrum measured under the beta source shows the X-ray beam generated by the interaction of the beta particles with the lead used to shield the source. Besides, the 59.4 keV gamma ray from 241Am was registered under the alpha source. Dose rates from 50 to 100 μGy/h were obtained for the dosimeter positions in the turntable under the beta and the alpha sources with the luminescent dosimeters.