Search Publications
Missions
Journals
Publication Years
The pulsation of the outer layers of the BET Cep-type variable BW Vul.
Sato, N.; de Jager, C.; Burger, M. +1 more
Eleven high-resolution ultraviolet spectrograms of BW Vul were obtained by means of the IUE over 1.6 periods to compare the pulsation of this star as observed in the strong far-UV resonance lines with observations of the UV lines of photospheric origin. The radial velocity curve of the C IV lines is different from the photospheric one, showing tha…
The MG II resonance lime emission at 2800 angstrom in stars with different rotational velocities and different metal abundances.
Boehm-Vitense, E.
In many investigations, a study of the Mg II 2800 A emission was conducted in order to derive more information about the correlation of chromospheric emission with the properties of the convection zone. It has been suggested by Ayres and Linsky (1980) that there is a positive correlation between rotation and chromospheric emission at least for bin…
The variable shell star HR 5999.
Hack, M.; The, P. S.; Tjin A Djie, H. R. E. +1 more
High and low resolution IUE spectra of the Herbig Ae-type star HR 5999 show strong emission lines of H, O I, C II, C IV, Mg II and possibly C III, N I and O V, and numerous shell absorption lines, mainly of Fe II, Cr II, Mn II and Ni II. The presence of strong emission lines due to hot gas suggests that Hr 5999 has a chromosphere and a corona, pro…
Ground based and IUE spectral observations of AU Mon.
Sahade, J.; Ferrer, O. E.
Results of ground-based and IUE spectral observations of the close binary AU Monocerotis made in January 1979, are reported. The ground-based observations made in the spectral regions 3600-4500 and 4900-7200 A show radial velocities and H-alpha emission suggestive of radial outflow from a subgiant component at high velocities, and from a B5 primar…
Ultraviolet and X-ray observations of the BL Lac PKS 0548-322.
Kondo, Y.; Mushotzky, R. F.; Urry, C. M. +2 more
Spectrophotometric observations of the BL Lac object PKS 0548-322 were made with ultraviolet and X-ray instruments on the IUE and HEAO-2 satellites. Two observations in each spectral region, one set of which was obtained simultaneously are presented. A power law of energy index approximately 1.0 gives a good description of the data from ultraviole…
The UV continuum spectrum of M81
Torres-Peimbert, S.; Peimbert, M.; Bruzual A., G.
From IUE data the absolute continuum spectrum for the nucleus of M81 in the 1200-3200 A range is presented. The spectrum can be fitted by an old stellar population with a small contribution from horizontal-branch stars. It is found that the number of stars with m less than 0.3 solar mass is negligible. An upper limit for the nonthermal contributio…
Evidence for mass loss at polar latitudes in the Be stars Omega Orionis and 66 Oph
Peters, G. J.
IUE observations of the pole-on Be stars Omega Ori and 66 Oph have revealed the unexpected presence of high velocity (-250 to -850 km/sec), relatively narrow (about 1 A) absorption components to the resonance lines of C IV, Si IV, and Si III. The C IV features show structure indicative of multiple shells or clouds. If Omega Ori and 66 Oph are inde…
Analysis of the IUE and optical spectra of the peculiar Be star HD 87643.
Pottasch, S. R.; de Freitas Pacheco, J. A.; Gilra, D. P.
IUE observations of the peculiar Be star HD 87643 are presented. The broad absorptions seen at 2400 A, 2600 A, and 2750 A are interpreted as being produced by Fe II transitions from the ground-state and the low lying metastable states. The optical lines of Fe II seen in emission are most probably excited by continuum fluorescence. This interpretat…
The ultraviolet spectrum of KQ PUP (Boss 1985).
Altamore, A.; Viotti, R.; Giangrande, A.
The high resolution spectrum of the VV Cep star KQ Pup observed with the IUE satellite during 1979 and 1980 is summarized. More than 600 lines have been identified between 1190 and 3228 A. Two main line systems are present, a broad absorption line system, which includes high ionization lines from N V, C IV, Si IV and Al III, and narrow P Cygni lin…
Interstellar extinction in the Perseus arm.
Nandy, K.; McLachlan, A.; Morgan, B. L.
Individual UV extinction curves for nine stars located in the direction of h and Chi Persei in the distance range 0.6-4.4 kpc are presented. The observations were made with the International Ultraviolet Explorer (IUE) in the low dispersion mode with large aperture. The sample has been enlarged by the use of available UV and visible data for 32 red…