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We discuss joint observations of flares on the dMe star AD Leo made with IUE, the VLA, and the Tinsley photometer at the University of Hawaii's 24-inch reflector on Mauna Kea. We find that optical emission is correlated with C IV while radio emission is better correlated with He II. We reach some tentative conclusions concerning timescales and source characteristics.
During September and November 1986 a light curve was recorded for the RS CVn star II Peg which was of an unprecedentedly large amplitude (Byrne, 1986). During December two moderately high resolution (∼25000) Hα spectra were obtained, one at light maximum, the other near light minimum. Analysis of the light and colour curves indicates that at least 16% of the star's surface was spotted. The Hα spectra...
Broad-band photometric observations of YZ CMi show a 1.2 magnitude U-band flare at 19:55 UT on 4 March 1985. During the flare the Ca I feature at 4227A changed dramatically. In the spectrum taken during the rise phase, Ca I was both narrower and weaker than that of either the preflare spectrum or spectra taken later in the flare. We interpret this as evidence that the photospheric flare continuum...
Broad-band photometric observations of YZ CMi show a 1.2 magnitude U-band flare at 19:55 UT on 4 March 1985. During the flare, optical spectra show excess emission in the wings of all the hydrogen Balmer lines. Interpreted in terms of mass flows would imply material moving at ∼300 km s−1 simultaneously to the blue and red or alternatively random mass motions with a velocity of a similar magnitude...
We report on an analysis of flaring and BY-Draconis type variability on the Balmer emission line star, Gliese 867B. The time-averaged flare energy in the Johnson 1-band is similar to that measured in 1977 and 1978. A variation of 0.15 magnitudes was observed in the V-band with a period l.95 days.