Application of Solid State Detectors to High Energy Physics

All charged particles exhibit a minimum in their - dE/dX versus E behaviour. This minimum occurs at relativistic velocities, i.e. high energies, and corresponds to an energy loss of approximately 1.7 Mev gm-1 cm2 for all particles. The application of solid state detectors at high energies depends on obtaining good signals from these minimum ionizing events. Detectors for this application should be large in area, have reasonably thick depletion layers, and a low series resistance to insure fast rise time. Low noise is not a prime requirement however, since the Landau effect in any case limits the resolution to a low value. Using an analyzing magnet and counter telescope at the Brookhaven Cosmotron, diffused silicon junctions of up to 1.5 cm diameter have been investigated using minimum ionizing particles. The signal-to-noise ratio obtained is ~ 10:1 and the resolution ~ 30%.