A Solar and Galactic Cosmic Ray Satellite Experiment

A cosmic ray instrument for NASA´s OGO-F spacecraft is described. The experiment consists of three charged particle detector systems which are designed to measure the spectra and chemical composition of galactic and solar cosmic rays over selected energy intervals. Two of the detector systems, the ¿E-Range and ¿E-¿erenkov telescopes, will measure the galactic flux and smaller solar flare fluxes, while a third detector system, the Flare telescope, will measure larger fluxes The three telescopes identify particle energy and type by various techniques. Energy loss and range, which provide the identification of protons (1 to 300 MeV), alpha particles (4 to 1200 MeV) and electrons (1 to 500 MeV), are measured in a stack of silicon solid state detectors and tungsten absorbers in the ¿E-Range telescope, while the identification of protons (350 to 1000 MeV), alpha particles (1400 to 4000 MeV) an, nuclei through oxygen is provided in the ¿E-¿erenkov telescope by energy loss measurements in silicon solid state detectors and a velocity measurement in a quartz & ¿erenkov radiator. The Flare telescope employs a double energy loss measurement in silicon detectors for the identification of protons (17 to 100 MeV) and alpha particles (70 to 400 MeV). The design of the instrument is optimized for maximum use of the available data rate with minimum weight, volume and power requirements.