Analytical investigation of energy spectrums of beta rays emitted from Sr-90 and Tl-204 radioisotopes

The energy spectra of beta rays emitted from Sr-90 and Tl-204 radioisotopes were obtained by using a silicon surface barrier detector with a 1000 mu m depleted layer and 50 mm(2) effective area. The detector response function is interpreted by making use of range distributions of mono-energetic electrons in matter and by assuming a linear energy loss along the range in the depleted layer of the detector. An analytical expression is given for pulse height distribution obtained in the surface barrier detector. A good agreement is observed between the experimental results and theoretical interpretation