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A Catalog of X-Ray Spectra of BL Lacertae Objects
Bassani, L.; Ciliegi, P.; Caroli, E.
This paper contains a list of X-ray spectra of BL Lac objects mostly collected from the literature. For a small sample of objects EXOSAT/ME spectra have also been analyzed and included in this list. In the catalog 42 objects are considered (26 radio selected and 16 X-ray selected) for a total of 311 X-ray spectra. For each object we report the X-r…
Extended Variability of the Symbiotic Star AG Draconis
Kafatos, M.; Meier, S. R.; Martin, I.
High and low resolution IUE satellite observations of the symbiotic star AG Draconis covering the period 1979-1989 are presented, and the far-UV spectra are studied. Two extended outburst events are found to have two maxima separated by about 1600 days, a time scale not known to be associated with the star but which is about three times the binary…
Electron Density Diagnostics for Gaseous Nebulae Involving the O IV Intercombination Lines near 1400 Angstrom
Feibelman, W. A.; Keenan, F. P.; Conlon, E. S. +2 more
The Bloom and Pradhan (1992) results on the excitation rates for transitions in O IV matrix are used to derive emission-line ratios near 1400 A, applicable to gaseous nebulae. The results are compared with the values measured from high-resolution spectra obtained by the IUE satellite.
Far-Ultraviolet Stellar Photometry: A Field in Orion
Schmidt, Edward G.; Carruthers, George R.
Far-ultraviolet photometry for 625 objects in Orion is presented. These data were extracted from electrographic camera images obtained during sounding rocket flights in 1975 and 1982. The 1975 images were centered close to the belt of Orion while the 1982 images were centered approximately 9 deg further north. One hundred and fifty stars fell in t…
The Extreme Ultraviolet Spectrograph: A Radial Groove Grating, Sounding Rocket--borne, Astronomical Instrument
Wilkinson, Erik; Green, James C.; Cash, Webster
The design, calibration, and sounding rocket flight performance of a novel spectrograph suitable for moderate-resolution EUV spectroscopy are presented. The sounding rocket-borne instrument uses a radial groove grating to maintain a high system efficiency while controlling the aberrations induced when doing spectroscopy in a converging beam. The i…
Model Atmospheres: Tool for Identifying Interstellar Features
Frisch, P. C.; Slojkowski, S. E.; Rodriguez-Bell, T. +1 more
Model atmosphere parameters are derived for 14 early A stars with rotation velocities, from optical spectra, in excess of 80 km/s. The models are compared with IUE observations of the stars in regions where interstellar lines are expected. In general, with the assumption of solar abundances, excellent fits are obtained in regions longward of 2580 …