USE OF PIXEL DETECTORS IN ELEMENTARY PARTICLE PHYSICS

Silicon pixel detectors allow measurement of charm and bottom decays, which have mean rest-frame decay lengths in the range 60-360-mu-m. Because of the high particle density which can be accommodated by detectors with pixel size 30-mu-m X 30-mu-m, direct measurement of decay paths should be possible in future fixed-target experiments. At high energy hadron colliders like the SSC and LHC and at e+e- colliders operating at the Z0 resonance the two particle separation will be of order 70-mu-m at the inner barrel. Such a high track density can best be accommodated with pixel detectors. A prototype readout chip for a pixel detector has been submitted for fabrication by an SSC R&D collaboration. This chip contains a random access array of 32 x 64 cells of dimension 45 x 150-mu-m. Each cell has analog and digital storage. The performance goal is 300 electrons rms noise at 20-degrees-C and full charge collection in 50 ns.