Search Publications
EXOSAT Observations of X-Rays from Classical Novae during Outburst Stage
Beuermann, K.; Krautter, J.; Ögelman, H.
The initial discovery of soft X-rays from Nova Muscae 1983 was followed by eight additional observations of the three brightest novae whose outburst stage coincided with the lifetime ofEXOSAT satellite; namely three more observations of Nova Muscae 1983, three observations of Nova Vulpeculae 1984#1 (PW Vul), and two observations of Nova Vulpeculae…
X-Ray Observations of the Supernova Remnant N103B in the Large Magellanic Cloud
Singh, K. P.; Westergaard, N. J.; Schnopper, H. W. +1 more
New X-ray observations of the supernova remnant N103B made using the European X-Ray Observatory satellite Exosat and the Einstein Observatory are reported. An X-ray map from Exosat obtained with three different filters corresponding to three different energy bands is presented. The analysis of the X-ray spectra indicates a thermal origin for X-ray…
Observations of active galaxies
Mushotzky, Richard
New information obtained by the EXOSAT satellite on the nature of the X-ray variability in AGNs is discussed. From the EXOSAT data, it is seen that many more AGNs vary on short timescales; in some cases, the character of the time variability is quantitatively and qualitatively different than expected from the flare model of the variability. Data o…
The Ultraviolet Variability of AY Ceti
Sonneborn, George; Simon, Theodore
AY Cet is a single-line binary comprised of a spotted G5 III primary and a white dwarf secondary. The authors obtained a series of UV spectra with the IUE satellite on five different dates covering a substantial part of the optical cycle of the primary star. They found no evidence that the continuum or the Lyα absorption line of the secondary star…
The Stars with H alpha Missing
Downes, Ronald A.
During the course of a survey for ultraviolet-excess objects, a group of objects were found that spectroscopically resemble the subdwarf B stars, except for variable strength H-alpha absorption. The H-alpha line can have the nominal strength predicted from the other Balmer lines, or it can be completely absent. Observations reveal significant chan…
The ultraviolet spectrum of the peculiar emission-line star GG Carinae : the line identifications.
Gosset, E.; Brandi, E.
Line features as well as the continuum of GG Carinae in the ultraviolet wavelength domain were described by Brandi et al. (1986) on the basis of a series of high and low resolution IUE spectra for which the line identifications are detailed here. The present contribution is thus the complement to the above-mentioned paper and enables the disentang…
Element Identifications in the UV Spectrum of HR 465
Fuhrmann, K.
High resolution IUE spectra of HR 465 were investigated. Line identifications for C, N, Eu, and Pt are presented, the occurrence of some other elements discussed.
The bright QSO GD 1339.
Kollatschny, W.; Fricke, K. J.; Bues, I. +1 more
Multifrequency observations of the radio-quiet QSO GD 1339 have been obtained using the EXOSAT, IUE, and ESO telescopes. The redshift of GD 1339 is z = 0.116 and its apparent magnitude mv = 15m.2. This bright nearby QSO may be suitable for detailed follow-up studies and as a spectroscopic reference source.
The Fe II emission in the UV spectrum of CH Cyg.
Selvelli, P. L.; Marsi, C.
Fe II emission lines are present in all UV spectra of CH Cyg, with a great increase in number and intensity since 1985. The authors give a list of emission intensities and equivalent widths for the prominent Fe II lines. Optical depth effects are clearly evident from a comparison of the relative emission intensities within couples of multiplets wh…
Search for the circumstellar envelopes around the late-type binary systems.
Glebocki, R.; Sikorski, J.
For 21 G and K type binary systems of luminosity class II-IV analysis of Mg II emission lines based on the IUE archive data is performed in order to establish the main contributor to the h3 and k3 absorption features. Asymmetry of the emission as well as shift of absorption relative to the emission center can be used as an in…