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A coordinated search for flares from the dMe star YZ Canis Minoris was performed in 1979 October using the Einstein Observatory and ground-based optical and radio telescopes. An event was detected in the optical, radio, and X-ray wavebands on October 25, and a second optical event on October 27 was seen as a marginal (2

/UEobservationsofthelatetypestar RWHya(gM2 +pee) have been obtained. Analysis of the intense UV continuum observed between 1100 and 2000 A suggests that this object is a binary system in which the secondary is identified as the central star of a planetary nebula with Terr "' 10 5 K. The ultraviolet spectrum is characterized by semiforbidden and allowed transition lines, of which the C IV (1548 A, 1550 A) doublet is particularly strong. A general absence of strong forbidden line emission suggests that the compact nebula in which both primary and secondary stars are embedded has particularly high densities of "'10 8-10 9 em-3. Tidal interaction rather than steady state mass flow from the M giant is suggested as a means to form a nebula with the characteristic densities inferred from our UV line analysis. RW Hya is suggested as a possible source of soft X-ray emission if material is accreting onto the surface of the secondary. A general discussion concerning the ionic abundances of various atomic ions present is given.

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IUE observations of R Aquarii (M7 + pee) have been obtained in low dispersion in order to study its circumstellar emission. Strong permitted, semiforbidden, and forbidden emission lines are identified that are superposed on a bright ultraviolet continuum. From our analysis we deduce that the strong emission-line spectrum that involves C III], C IV, Si III], [0 II], and [0 III] probably arises from a dense compact nebula the size of which is comparable to the binary system of which R Aqr is the primary star. Low-excitation emission lines of Fe II, Mg II, 0 1, and Si II suggest the presence of a warm chromosphere (T ~ 10,000 K) in the primary M7 late type giant. We identify the secondary as a white dwarf, comparable to or somewhat brighter than the Sun, since such a star can produce enough ionizing photons to excite the continuum and emission-line spectrum and yet be sufficiently faint to escape detection by direct observation. The UV continuum observed is attributed to Balmer recombination and not to blackbody emission from the hot companion. The general spectral properties of R Aqr between 1200 A and 3200 A are discussed in the context of our model for the circumstellar nebula, the companion, and the mass-loss rate of the primary star.