Proton telescope (PROTEL) on the CRRES spacecraft

The design and operation of the proton telescope (PROTEL) on the Combined Release and Radiation Effects Satellite (CRRES), which operated in a low-inclination, geosynchronous transfer orbit from 25 July 1990 to 12 October 1991, are described. PROTEL makes well-calibrated, high-angular-resolution measurements of the proton differential energy spectrum once per second from 1 to 100 MeV in 24 channels. The instrument contains silicon solid-state detector arrays with both anticoincidence and multiple coincidence requirements to reduce contamination. The detector and channel characteristics derived from an extensive calibration program are provided, and initial performance and data analysis are discussed.>