Chronology of generation, variation, and disappearance of a second proton belt as determined by effects in electronic devices

The paper presents an analysis of SEU data obtained from memory devices on the CRRES (Combined Release and Radiation Effects Satellite) spacecraft. It provides a dynamic picture of the newly identified second peak of the trapped proton belt in the equatorial region between approximately 2.0-2.8 Earth radii. In previous work, it was stated that injection of solar flare protons from the major flare of March 1991 generated this secondary belt which appears to have survived at least up to the demise of CRRES (October 12, 1992). The results of the present study show that the radiation responsible for the observed effects existed intermittently in that region of space from the very beginning of the mission, that is July 27, 1990, during a period when there was no significant high energy flare activity (about 4.5 months), and then disappeared for three months until it reappeared again with the March 1991 flare.