Search Publications
Mesures de vitesses radiales. VII. Accompagnement AU sol du programme d'observation du satellite Hipparcos. Radial velocities. VII. Ground based measurements for Hipparcos.
Duflot, M.; Burnage, R.; Genty, V. +2 more
We publish 734 radial velocities of stars distributed in 28 fields of 4x4deg. We continue the PPO series (Fehrenbach et al. 1987; Duflot et al. 1990 and 1992), using the Fehrenbach objective prism method.
Broad NE VIII lambda 774 Emission from Quasars in the HST-FOS Snapshot Survey (ABSNAP)
Hamann, Fred; Tytler, David; Zuo, Lin
We discuss the strength and frequency of broad Ne VIII λ774 emission from quasars measured in the HST-FOS snapshot survey (Absnap). Five sources in the survey have suitable redshifts (0.86 <= z_em_ <= 1.31), signal-to-noise ratios and no Lyman limit absorptions. Three of the five sources have a strong broad emission line near 774 A (rest), a…
Ulysses Radio and Plasma Wave Observations at High Southern Heliographic Latitudes
Goetz, K.; Kellogg, P. J.; MacDowall, R. J. +17 more
Ulysses spacecraft radio and plasma wave observations indicate that some variations in the intensity and occurrence rate of electric and magnetic wave events are functions of heliographic latitude, distance from the sun, and phase of the solar cycle. At high heliographic latitudes, solar type III radio emissions did not descend to the local plasma…
HD 93521, zeta Ophiuchi, and the Effects of Rapid Rotation on the Atmospheres and Winds of O9.5 V Stars
Massa, Derck
Both low- and high-resolution IUE spectra of the rapidly rotating 09.5 V stars HD 93521 and zeta Oph are used to develop a coherent picture of the effects of rapid rotation on the atmospheres and winds of late, main-sequence O stars. The observational consequences are by far the strongest on HD 93521, most likely because it is being viewed nearly …
N IV Emission Lines in the Ultraviolet Spectra of Gaseous Nebulae
Feibelman, W. A.; Keenan, F. P.; Berrington, K. A. +4 more
Theoretical electron density sensitive emission-line ratios, determined using electron impact excitation rates calculated with the R-matrix code, are presented for R = I(2s2 (1)S-2s2p 3P2)/I(2s2 (1)S-2s2p 3P1 = 1(1483 A)/I(1486 A) in N IV. These are found to be up to an order of magnitude different from …
Recent Changes in the IUE Spectrum of the Very Young Planetary Nebula He 3-1357 (=SAO 244567)
Feibelman, Walter A.
We obtained the first high-dispersion IUE spectrum, and an additional low-dispersion spectrum of the very young planetary nebula He 3-1357 and its central star SDAO 244567. In 1988, it showed a very strong C IV lambda-1549 P Cygni profile which diminished and has disappeared by 1994, but C IV absorptions are seen in a high-resolution spectrum. The…
Discovery of a white dwarf companion (EUVE J0254-053) to the K0 IV star HD18131
Doyle, J. G.; Mathioudakis, M.; Byrne, P. B. +2 more
New ultraviolet (UV) observations of late-type stars detected in the Extreme Ultraviolet Explorer (EUVE) all-sky survey revealed an unsuspected white dwarf companion to the K0 star HD18131. The International Ultraviolet Explorer (IUE) spectrum show a composite of a white dwarf and a late-type star. The white dwarf dominates the emission below 2000…
Over the Southern Solar Pole: Low-Energy Interplanetary Charged Particles
Simnett, G. M.; Pick, M.; Anderson, K. A. +11 more
The heliosphere instrument for spectrum, composition, and anisotropy (HISCALE) recorded the fluxes of low-energy ions and electrons (>50 kiloelectron volts) when Ulysses crossed the southern solar polar region and revealed that the large-scale structure of the heliosphere to at least ~-75^circ was significantly influenced by the near-equatorial…
Neutral Sulfur Emission from the Io Torus Measured with the Hopkins Ultraviolet Telescope
Blair, William P.; Feldman, Paul D.; Kriss, Gerard A. +5 more
During the Astro 1 mission in 1990 December, ultraviolet spectra of the Io plasma torus were obtained using the Hopkins Ultraviolet Telescope. These spectra cover a wavelength range of 830-1860 Å in first order and 415-930 Å in second order. Two separate observations were made. Observation 1, which nominally contained Io within the aperture, cente…
Chemical abundances of southern symbiotic stars.
Pereira, C. B.
Allen's (1984) optical spectra of symbiotic stars were used in order to derive some elemental ratios and He abundances. The studied systems were those for which spectrophotometry was available in his catalogue, i.e. LMC S63, Y Cra, SS 29, He2-104, SS 38, He2-106, V455 Sco, He2-127, He2-171, AE Ara, SS 122 and Hen 1242 (=KX TrA). Estimates for the …