Equipment for beta detection and measurement using Si detectors

The specifications and characteristics are given of an equipment with Si detectors for 32P beta detection and measurement. Low-noise Si detectors, a low-noise charge-sensitive preamplifier, a linear pulse amplifier with optimum pulse shaping increasing the recording efficiency of the individual pulses, and a multiple stabilized power supply with high stability and low ripple were used in the design. The equipment developed allows scanning and determination of radioactivity distribution after gel electrophoresis and radiochromatogram evaluation by the line method. In comparative evaluations the same efficiency was obtained for large-surface Si detectors as for the methane or propane detection probe for 32P and 86Rb with a Czechoslovak-made detector and preamplifier ORTEC 142 B. (B.S.)