Search Publications
UV observations of the BL Lac object 0716+71.
Kollatschny, W.; Fricke, K. J.; Schleicher, H.
UV observations acquired by the IUE satellite of the BL Lac object 0716+71 are presented. Data were obtained in both the long- and short-wavelength ranges (2400-3000 and 1250-1900 A) and reduced using the spatially resolved line by line spectrum and the geometrically and photometrically corrected image in view of the very low signal-to-noise ratio…
The transition region structure of kap Cet.
Rego, M.; Fernandez-Figueroa, M. J.; de Castro, E.
Ultraviolet emission lines of Kappa Ceti (HD 20630), obtained with the IUE satellite, are analyzed in order to study the higher chromospheric, transition region and the low corona structure. Three models are derived for the emission measurement distribution, and the best fit model has a pressure of log Pe equals 14.96 at log Te
UV observations of the intermediate helium star CPD -46 3093.
Heber, U.; Hunger, K.
UV spectrograms of CPD-46 deg 3093 have been obtained with IUE in low resolution. No evidence for mass loss can be found at this resolution. A synthetic spectrum, calculated in LTE and including 800 atomic transitions matches the observations. Also the UV Si III/Si IV ionization equilibrium is reproduced as well as the Stromgren colors. The atmosp…
IUE and optical observations of V861 Sco.
Howarth, I. D.; Wilson, R.; Burger, M. +7 more
We present the first results of high dispersion (Δλ ≃ 0.2 Å) IUE spectra of the possible X-ray binary V 861 Sco (HD 152667) taken at several orbital phases. Contemporary optical spectroscopy, uvbyβ and infrared photometry are also reported.
The UV spectrum is quite normal for the spectral type (B0Ia), with P Cygni profiles on a number of line…A high resolution IUE spectrum of the GO-GSIA supergiant HR 8752.
Stickland, D. J.; Lambert, D. L.
A high-resolution long-wavelength IUE spectrum of the G0-G5Ia supergiant HR 8752 and its B main sequence companion is discussed. The supergiant, which dominates for wavelengths greater than approximately 2700 A, appears to have a normal spectrum. The spectrum of the B star contains several deep asymmetric absorption lines. It is argued that these …
Narrow ultraviolet absorption lines of nova CYG 1978.
Friedjung, M.
The narrow Fe II and Mn II absorption lines observed by the IUE satellite have been studied by the curve-of-growth method. Data on the line of sight column densities, including the Fe II/Mn II and the nonexcited Fe II/slightly excited Fe II ratios, have been obtained. It is shown that the line wavelength shifts and the physical characteristics of …
Far-UV wind line profile changes in the O-type star HD 175754.
Stalio, R.; Carrasco, L.; Costero, R.
Resonance line profile changes in far-UV spectra of HD 175754, obtained with the IUE satellite are reported. These changes are interpreted in terms of variations in the dynamics and density-ionization structure of the star's wind.
Erratum - IUE Observation of Strong Ultraviolet Absorption in the Spectrum of the c2 White Dwarf L145-141
Koester, D.; Vauclair, G.; Wiedemann, V.
Photometric calibration of the international ultraviolet explorer (IUE) : low dispersion.
Savage, B. D.; Snijders, M. A. J.; Bohlin, R. C. +2 more
Absolute sensitivity curves for IUE low-resolution spectra are obtained by comparing IUE measurements of hot stars with the absolute energy distributions established for these objects by previous satellite and rocket experiments. The differences between these earlier experiments are discussed quantitatively, and a common absolute flux scale is pro…
Detailed characteristics of the high-energy gamma radiation from PSR 0833-45 measured by COS-B.
Bignami, G. F.; Hermsen, W.; Masnou, J. L. +11 more
A series of COS-B observations of the high-energy gamma-ray emission from PSR 0833-45 has been combined to derive detailed temporal and spectral characteristics of this source. The gamma-ray period of the pulsar was determined for the observations spanning the time interval October 1975 to June 1977. The variation of the period with time can be ex…