Probability of large solar proton events and their effect on the efficiency of GaAs solar cells

✍ Scribed by M. A. Xapsos; S. R. Messenger; R. J. Walters; G. P. Summers; E. A. Burke

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 147 KB
• Volume: 6
• Category: Article
• ISSN: 1062-7995
• DOI: 10.1002/(sici)1099-159x(199811/12)6:6<399::aid-pip222>3.0.co;2-d

✦ Synopsis

Using a recently updated database that includes the last four complete solar cycles, the probability of occurrence of large solar proton events has been analyzed for time periods of up to seven active solar years using extreme value statistics. Then an approach is presented for evaluating solar cell eciency degradation caused by the large event. These results enable spacecraft designers to evaluate precisely the risk of exposure of solar arrays to large solar proton events over the course of a mission. As an example, the eciency degradation of n/p GaAs/Ge solar cells caused by an event with a 410-MeV ¯uence of 1 Â 10 10 cm À2 is shown. This is compared to the degradation resulting from all events in the last solar cycle, and to the electron environment in geostationary orbit over the same period of time.