R Aquarii

R. Viotti and L. Rossi, Istituto Astrofisica Spaziale, Frascati; A. Cassatella, European Space Agency and IUE Observatory, Villafranca; and L. Piro, Istituto TESRE, Bologna, telex: "The symbiotic Mira-type variable R Aqr was observed with EXOSAT on 1985 Dec. 24 near the Mira light minimum. The x-ray flux appears weak and close to that detected in 1985 June (IAUC 4083). Coordinated IUE observations of R Aqr and its jet made at Vilspa on Dec. 23 show no large changes in the ultraviolet spectrum with respect to previous 1985 observations and confirm a higher temperature for the jet (IAUC 4157). These results indicate that x-rays do not originate from the Mira giant, but rather in the circumstellar region of a hot companion. Reanalysis of the previous 1980 Einstein Observatory observations suggests that the marginal detection (Jura and Helfand 1984, Ap.J. 287, 785) actually is only an upper limit."