Ultraviolet flares on II Pegasi.
Doyle, J. G.; Byrne, P. B.; van den Oord, G. H. J.
United Kingdom
Abstract
UV spectroscopic observations of the RS CVn star, II Peg, were obtained in February 1983. The observations show evidence for flare activity in greatly enhanced chromospheric and transition region emission lines. The flare radiation is isolated and the electron pressures of the mean quiescent atmosphere and the two flares are derived from the intersystem line flux ratios. Estimates are given of the total flare power output over the whole atmosphere and the surface filling factor for the flares. The implications of the observations for studies of flares on RS CVn stars are considered.