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Fe II Fluorescence and Anomalous C IV Doublet Intensities in Symbiotic Novae
Kafatos, M.; Michalitsianos, A. G.; Meier, S. R.
The variation of absolute intensities of Bowen-excited Fe II emission in the symbiotic stars RR Tel, RX Pup, and AG Peg is examined. The C IV doublet intensity ratios in RR Tel were not anomalous between 1979 and 1989, and the ratio had typical values within the optically thin range. The intensity of individual Fe II Bowen-excited lines is correla…
X-Ray Continuum and Line Emission of the Seyfert Galaxy MCG-5-23-16
Singh, K. P.; Rao, A. R.; Vahia, M. N.
We report observations of X-ray continuum and line emission from the highly absorbed and variable Seyfert galaxy MCG -5-23-16, using the low- energy and the medium-energy detectors of the EXOSAT Observatory. The galaxy was observed in 1983 December and in 1984 May. The X-ray intensity of the source is observed to vary by ~25% in the hard (2-10 keV…
X-Ray to Infrared Observations of the Cataclysmic Variable KO Velorum (E1013-477)
Maraschi, L.; Chiappetti, L.; Motch, C. +6 more
Simultaneous photometric and spectrometric observations of the source E1013 - 477 in X-ray, UV, optical, and IR bands are presented. Evidence is found in support of the recently proposed orbital period of 10.12 hr. The X-ray spectra (0.1-10 keV) are well fitted by a single power law of photon index -0.8 with interstellar absorption NH not greater …
Ultraviolet Observations of the Symbiotic Star AS 296
Feibelman, W. A.; Moreno, H.; Gutierrez-Moreno, A.
AS 296 is a well-known S-type symbiotic star which underwent an optical outburst during 1988. In this paper, UV data based on IUE observations obtained both during the quiescent and outburst stages are presented and discussed, correlating them to observations made in the optical region. It is concluded that the object is a symbiotic nova, in which…
Properties of the SN 1987A Circumstellar Ring and the Distance to the Large Magellanic Cloud: Erratum
Panagia, N.; Kirshner, R. P.; Macchetto, F. +2 more
Figures 2 and 3 of the Letter "Properties of the SN 1987A Circumstellar Ring and the Distance to the Large Magellanic Cloud," by N. Panagia, R. Gilmozzi, F. Macchetto, H.-M. Adorf, and R. P. Kirshner (ApJ, 380, L23 [1991]), contained some errors; i.e., Figure 2 had the wrong theoretical curve as a fit to the time evolution of the C III)λ1909 line …
Seyfert Galaxy Ultraviolet Emission-Line Intensities and Variability: A Self-consistent Photoionization Analysis Applied to Broad-Line--emitting Gas in NGC 3783
Koratkar, Anuradha P.; MacAlpine, Gordon M.
Both strong and weak ultraviolet emission lines in SeYfert 1 galaxies have been accurately measured from reextracted short-wavelength camera data in the IUE satellite data archives. Line ratios, equivalent widths, and trends as functions of continuum variability were used to constrain numerical modeling parameters in detailed photoionization analy…