Use of a Si(Li) detector as ß spectrometer.

ABSTRACT

The aim of this work is to demonstrate the capability of a Si(Li) detector for the measurement of ß spectra, despite the energy absorption in air and in the Be window. A simple source holder fixes the source on the symmetry axis at 3mm from the detector window. The ß-sources are produced by evaporation on a plastic backing plate. Absorbing materials between the source and the sensitive volume of the detector are 3 mm of air, a Be window, 0.1 µm Si and 20 nm of gold. A model of the detector was created for ß spectra simulation using the MCNP 4A code. Experimental spectra of (14)C, (147)Pm, (204)Tl, (90)Sr/(90)Y were compared with simulated spectra.