Silicon Surface-Barrier Nuclear Particle Spectrometer

Gold silicon surface-barrier counters which give good resolution at room temperature have been made. Counters from 150 ohm-cm material have given 15-kev (~1/4 per cent) resolution for Cm244 (5.801 mev) and Am241 (5.477 mev) alpha particles. A large-area 1-cm2 counter has given 0.7 per cent resolution for Po210 (5.30 mev) alpha particles. The detector has resolved alpha particle groups which previously had been unresolved with Frisch-grid pulse-ion chambers.