Coordinated optical and ultraviolet observations of IM Pegasi

IUE spectra and optical observations of IM Peg obtained during the summers of 1985 and 1986 are analyzed. The modulations of the UV emission lines and the H-alpha, H-beta, and the CaII IR triplet (IRT) optical lines are examined. It is observed that: the UV emissin-line modulation increases as a function of height, H-alpha variability is related to stochastic events, H-beta displays excess absorption relative to a standard star, and the Ca IRT reveals a clear modulation with phase. It is noted that IM Peg corresponds to the solar paradigm used to explain RS CVn activity.