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Multi-frequency observations of the 1985 outburst of RS ophiuchi
Snijders, M. A. J.
The 1985 outburst of the bright, recurrent nova RS Oph was almost simultaneously observed at X-ray, UV, optical, IR and radio frequencies at many epochs. The abundances in the ejected shell and the development of the bolometric luminosity as a function of time suggest that the cause of the outburst is a nuclear runaway on a massive white dwarf.
Periodic Variabilities in the IUE Spectra of Ss-Cygni
Gaudenzi, S.; Giovannelli, F.; Lombardi, R.
The analysis of the IUE low resolution spectra of SS Cyg in quiescence clearly shows modulations with the orbital phase of the continuum and the emission lines total area. The shape of such modulations is depending on the type of the optical outburst preceding the quiescent phase in which the UV spectra were collected. This behaviour, together wit…
IUE observations of CH Cygni continuum during 1979–1986
Hack, M.; Mikolajewska, J.; Selvelli, P. L.
Variations of the UV continuum have been analyzed. The observed UV continuum may be reproduced by a superposition of a Kurucz model atmosphere (log g=2), Teff∼8500–15000 K) and optically thin hydrogen bound-free and free-free emission (Te∼ 1000 K). The temperature of the Kurucz atmosphere is the lowest at the maximum of brigh…
Continuum Distributions and Line Profiles of Ux-Ursae Type Nova like Systems
Haug, K.
Combined UV, optical and, in part, IR continuum distributions of the UX UMa-systems CPD-48°1577, V3885 Sgr, RW Sex and of the recently discovered cataclysmic system PHL 227 were determined from multi-wavelength spectroscopic and photometric data to search for general characteristics of these systems. The observed variations of the UV to IR spectro…
IUE Observations of Hl-Canis and the Winds of Cataclysmic Variables
Raymond, J. C.; Mauche, C. W.
As evidenced by the P Cygni profiles of their ultraviolet resonance lines, cataclysmic variables—like early-type stars—are known to have extensive, high velocity winds. Assisted by AAVSO visual data andIUE ultraviolet spectra, we present an observational and theoretical study of the P Cygni profiles of the dwarf nova HL CMa. As these profiles are …
Hot Wind in the Double Degenerate System Am-Canum
Kjeldseth-Moe, O.; Solheim, J. -E.
The close binary system Am CVn consists of two helium white dwarf stars in close orbit. Strong flickering in the optical light curve and the observed spin-up in the rotation period indicate that mass transfer takes place (Solheim et al., 1984). The optical spectrum shows broad helium absorption lines (Robinson and Faulkner, 1975) sometimes partly …
Combined satellite and ground-based observations of the quiescent, high latitude symbiotic variable AG Draconis=BD+67°922
Lambert, D. L.; Cassinelli, J. P.; Anderson, C. M. +1 more
Satellite observations, fromEinstein,IUE, andIRAS, have been combined with ground-based observations to derive the quiescent energy distribution of the symbiotic star AG Draconis. A detailed comparison is made between the combined observations and various steady-state composite models, including blackbody accretion disks.
A photometric and spectroscopic comparison of the cataclysmic variables on the 2 sides of the period gap and at a specific orbital period
Szkody, P.
New and previously existing photometric colors and spectroscopic H and He line strengths are used to compare CV disk systems below the period gap (P=80–130 min) with those directly above (P=190–240 min). Significant differences are found in the mean U-B, V-J colors and in the Hß equivalent widths on the 2 sides of the gap. A detailed comparison fr…
The may 1985 Super Outburst of Oy-Carinae - Part Two - Phase-Resolved IUE Spectroscopy and EXOSAT Observations
Sonneborn, G.; van Paradijs, J.; Charles, P. A. +4 more
We present ultraviolet and X-ray observations of the eclipsing SU UMa dwarf nova OY Car early in the decline from a superoutburst. From the UV emission line spectrum and lack of X-ray eclipse, we deduce the presence of an extended coronal region.
EXOSAT and IUE Observations of the Symbiotic Binary R-Aquarii during Maximum and Minimum
Piro, L.; Friedjung, M.; Viotti, R. +1 more
Coordinated IUE and EXOSAT observations of the symbiotic Mira R Aqr, made in June and December 1985, at phases 0.0 and 0.5 of the Mira light curve, are discussed. A weak X-ray flux has been for the first time unambiquously detected without any significant change with the Mira light curve. Also the UV spectrum of the central object has not varied, …