Two Satellite-Borne Cosmic Radiation Detectors

Cosmic radiation telescopes constructed at the University of Minnesota will be flown on the Polar Orbiting Geophysical Observatories, POGO C and D and on the Pioneer Deep Space Probes C and D. These experiments are designed to measure the differential energy spectra of protons, helium nuclei and heavy nuclei up to a charge Z=14 in the range 1.0 to 1200 Mev per nucleon. The POGO telescope utilizes a combination of scintillation and Cherenkov counters together with a semi-conductor detector. Use of the thresholds in the geomagnetic field extends the energy range for protons to 30 Bev. A Geiger tube, four lithium-drifted silicon detectors, and a Cherenkov counter comprise the Pioneer telescope.