Search Publications
Far UV variability of theta CrB in 1980-1985. II. Evidence for variability patterns and ionization dependence.
Stalio, R.; Doazan, V.; Thomas, R. N. +1 more
Far UV observations of Theta CrB obtained in 1980-1985 with the IUE are presented which provide evidence for long-term variability patterns associating the shape, velocity and strength of the Si IV, Al III, and Fe III lines. A differential variable behavior between lines arising from different ionization levels is also noted. The present results a…
Search for transition zone lines in early dwarf A stars.
Freire Ferrero, R.
The presence of hot external atmospheric layers in some A stars, demonstrated by the X-ray detections with the Einstein satellite, stimulated the search for optical counterparts, in particular, the search for the UV transition zone indicators like Si IV, C IV and He II lines. The observations of a sample of early dwarf A stars with IUE allows one …
The first near-UV observation of P/Halley
Ip, W. -H.; Bertaux, J. L.; Wallis, M. K. +9 more
Comet Halley was observed on April 1, 1985 with the long wavelength camera of the IUE observatory. There is some indication that an OH emission was present at ≡3085 Å. This emission would correspond to an OH production rate of about a few 1028 molecules per second.
Search for ultraviolet emission lines from a hot gaseous halo in the edge-on galaxy NGC 4244.
Bowyer, S.; Deharveng, J. M.; Joubert, M. +2 more
Short and long wavelength IUE spectra of the halo region in the edge-on galaxy NGC 4244 are analyzed in order to identify evidence of line emission at the level of 0.000001 ergs per cu cm sr/s. Features are found at 1245 A and 1402 A, having peaks four times greater than the rms intensity fluctuations of nearby spectra. The spectral features are i…
The nitrogen abundance in Wolf-Rayet WC stars.
Schmutz, W.; Nussbaumer, H.
In order to confirm the presence of nitrogen in WC stars, the IUE spectra of the WC 8 star HD 192103 have been studied in the region 1230-1250 A. The fluxes in the spectra of HD 192103 were extracted using two different procedures: the method described by Ramella et al. (1983); and the background correction method of Schmutz (1985). It is demonstr…
The ultraviolet IUE spectrum of the population II horizontal-branch Astar HD 109995.
Leckrone, D. S.; Adelman, S. J.
Eight SWP and six LWP high dispersion IUE images of the field horizontal-branch A star HD 109995 have been averaged to increase the signal-to-noise ratio. The line density in the ultraviolet is greater than that of the optical region, but less than that of comparable Population I A stars. Many of the identified lines are those of Fe II. Lines of C…
In-flight analysis of IUE cross-disperser scattered light
Feldman, P. D.
The scattered light properties of the IUE (International Ultraviolet Explorer) cross-disperser gratings are investigated using in-flight data of the emission spectrum of Comet Bradfield (1979X). The scattering function in the vicinity of H I Lyman alpha at 1216 angstroms is found to be significantly lower than that derived from either the laborato…