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Very Short-Duration UV–B Optical Flares in RS CVn-type Star Systems


Gary A. Vander Haagen

Stonegate Observatory, 825 Stonegate Road, Ann Arbor, MI

Received February 11, 2013; revised March 13, 2013; accepted March 15, 2013


Very short duration UV–B optical flares were observed during a high-cadence search for conventional flares on three RS CVn type stars: AR Lac, II Peg, and UX Ari. A statistical criterion was developed for isolating these short-duration optical flares from random photon events. Five flares, ranging in duration from 30 to 85 ms with peaks 0.29–0.51 mag. above the mean, were detected within the 132 hours of monitoring time. The time resolution of the observations was 5 ms for AR Lac and 10 ms for II Peg and UX Ari.

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