Silicon Diode as an Alpha Particle Detector and Spectrometer for Direct Field Measurements (original) (raw)
2016, Radiation Protection Dosimetry
A miniature windowless silicon (Si) diode (4 mm 2) was evaluated as alpha particle detector and spectrometer for field measurements. Such detector would be useful in radiation surveys following nuclear or radiological events that involve contaminated individuals and surfaces with alpha-emitting radionuclides. The detector was irradiated with alpha particles from a 241 Am (2.3 kBq) and a 210 Po (9 kBq) source at source-detector distances (SDD) of 0.5, 1.0, and 1.8 cm. Measurements obtained under normal air pressure and temperature showed that the Si diode is useful for energy-resolved measurements of alpha particles under these conditions. For the Si diode, the energy resolution in terms of full width at half maximum (FWHM) was 281 keV, 148 keV, and 113 keV for the SSD of 0.5, 1.0, and 1.8 cm, respectively. The minimum detectable activity increased from 0.08 Bq to 0.83 Bq when the SDD increased from 0.5 to 1.8 cm for the Si diode.
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