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The observations of the X-ray source HZ Her/Her X-1.
Davis, R. J.; Howarth, I. D.; Hammerschlag-Hensberge, G. +15 more
The results of a campaign of monitoring HZ Her with the IUE satellite are presented. The spectrum and light variation outside of eclipse are consistent with the Milgrom and Salpeter model for emission from the X-ray heated photosphere of the primary. Near eclipse there is UV flux in excess of the prediction of the heated photosphere model, which s…
The detection of a companion star to the Cepheid variable eta Aql.
Doschek, G. A.; Mariska, J. T.; Feldman, U.
Ultraviolet spectra have been obtained with IUE of the classical Cepheid Eta Aquilae at several phases in the 7.18 day period. Significant ultraviolet emission is detected at wavelengths less than 1600 A, where little flux is expected from classical Cepheids. Furthermore, the emission at wavelengths less than about 1600 A does not vary with phase.…
IUE observations of the peculiar M giant HD 4174.
Sahade, J.; Stencel, R. E.
Ultraviolet spectra of the peculiar M giant HD 4174, which may possess a significant magnetic field, are shown to exhibit numerous high-excitation emission lines and no background continuum. Ionization equilibrium temperatures for species observed range from 6000 K (Mg II) up to 200,000 K (N v). Density diagnostics using line ratios indicate elect…
The abundance of carbon and magnesium in the Orion Nebula
Patriarchi, P.; Perinotto, M.
The Orion nebula has been observed in two positions with IUE (International Ultraviolet Explorer) in the low-resolution mode (about 7 A) and in the spectral range 1150-3200 A. Emission lines of C II, C III, O II, and He I have been measured and used to determine what is probably the first reliable abundance of carbon in H II regions. The logarithm…
Electron densities for six planetary nebulae and HM SGE derived fromthe CIII lambda 1907/1909 ratio.
Feibelman, W. A.; Hobbs, R. W.; Boggess, A. +1 more
Electron densities for IC 418, NGC 6572, IC 1297, NGC 3242, NGC 6818, NYC 3211, and HM Sagittae derived from high-dispersion IUE C III] spectrograms are consistently higher than those derived from either surface brightness measurements or forbidden line intensity ratios in the visible. The nebulae were selected for a range of excitation classes fr…
Ultraviolet, visual, and infrared observations of the peculiar Be star HD 45677.
Savage, B. D.; Sitko, M. L.
The peculiar Be star HD 45677 was observed at low and high resolution by the IUE, and nearly simultaneous optical and IR observations were obtained with ground-based telescopes. These data were used to produce a spectral energy distribution extending from 0.12 to 12.6 microns in order to investigate the conversion of UV to IR radiation in the circ…
The detection of a companion star to the Cepheid variable T Monocerotis
Doschek, G. A.; Mariska, J. T.; Feldman, U.
We have obtained ultraviolet spectra with the International Ultraviolet Explorer (IUE) spacecraft of the classical Cepheid T Mon at several phases in the 27 day period. Significant ultraviolet emission is detected at wavelengths less than 1600 A, where little flux is expected from classical Cepheids. Furthermore, the emission at wavelengths less t…
IUE observations of the continuous spectrum of the Orion nebula.
Patriarchi, P.; Perinotto, M.
The continuous spectrum of the Orion Nebula has been observed in two positions in the bright Huyghenian region with the IUE (International Ultraviolet Explorer) satellite with a resolution of about 7 A in the spectral range of 1150-3200 A. The illuminating stars Theta 1 Orionis C and Theta 2 Orionis A have been observed under the same conditions. …
Observations of R Aqr.
Johnson, H. M.
Observations of ultraviolet emission lines and continuum with the IUE observatory, H-alpha flux density and line profiles of H-alpha and forbidden O III lambda-5007 with the CTIO Fabry-Perot interferometer, and detection of the 85 GHz continuum with the 11 m dish of the NRAO are presented. Comments on their relation to previous work on R Aquarii a…
Long-slit spectroscopy in the rocket ultraviolet of the Orion nebula.
Bohlin, R. C.; Witt, A. N.; Stecher, T. P. +1 more
The study deals with the extensive nebulosity in the Trapezium region of Orion. An entrance slit was placed at the focal plane of rocketborne telescope, creating a long-slit spectrograph with a wavelength resolution of 22 A FWHM and a spatial resolution of 14 in. along the slit. Data reduction is outlined, the structure of the Orion Nebula is disc…