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The Ultraviolet Continuum Emission of Radio Galaxies. I. Description of Sources from the Hubble Space Telescope Archives
Baum, Stefi A.; Zirbel, Esther L.
This paper describes the UV continuum radiation in the range from 1400 to 3700 Å of radio galaxies. The analysis is deferred to the next paper in this series. The sample of radio galaxies was compiled by searching the Hubble Space Telescope (HST) archives for images taken with the Faint Object Camera (FOC) prior to 1993. Altogether the sample cons…
Broad Ne VIII λ774 Emission from Quasars
Hamann, Fred; Cohen, Ross D.; Shields, Joseph C. +3 more
Ne VIII λ774 is an important tracer of the high-ionization gas in QSOs. We examine the Ne VIII emission-line properties using new Hubble Space Telescope (HST)-FOS spectra of four sources, mean spectra derived from two QSO samples in the HST archives, and new photoionization calculations. The results support our previous claim that broad Ne VIII li…
Elemental composition of the January 6, 1997, CME
Hsieh, K. C.; Wurz, P.; Bochsler, P. +25 more
Using solar wind particle data from the CELIAS/MTOF sensor on the SOHO mission, we studied the abundance of the elements O, Ne, Mg, Si, S, Ca, and Fe for the time period around the January 6, 1997, coronal mass ejection event (CME). In the interstream and coronal hole regions before and after this event we found elemental abundances consistent wit…
On the HIPPARCOS photometry of chemically peculiar B, A, and F stars
Adelman, Saul J.
The Hipparcos photometry of the Chemically Peculiar main sequence B, A, and F stars is examined for variability. Some non-magnetic CP stars, Mercury-Manganese and metallic-line stars, which according to canonical wisdom should not be variable, may be variable and are identified for further study. Some potentially important magnetic CP stars are no…
The Lower Main Sequence of ω Centauri from Deep Hubble Space Telescope NICMOS Near-Infrared Observations
Paresce, Francesco; De Marchi, Guido; Pulone, Luigi +1 more
A 20" × 20" field located ~7' from the center of the massive galactic globular cluster ω Centauri (NGC 5139) was observed by the NIC2 camera of the Near-Infrared Camera and Multiobject Spectrometer on board the Hubble Space Telescope (HST) through the F110W and F160W broadband filters centered at 1.1 and 1.6 µm for a total of 3000 and 4000 s…
Joint Nancay Radioheliograph and LASCO Observations of Coronal Mass Ejections - II. The 9 July 1996 Event
Llebaria, A.; Michels, D. J.; Schwenn, R. +10 more
The development of a coronal mass ejection on 9 July 1996 has been analyzed by comparing the observations of the LASCO/SOHO coronagraphs with those of the Nancay radioheliograph. The spatial and temporal evolution of the associated radioburst is complex and involves a long-duration continuum. The analysis of the time sequence of the radio continuu…
Resolving the Intrinsic C IV Absorption in the Seyfert 1 Galaxy NGC 3516
Mushotzky, Richard F.; Crenshaw, D. Michael; Maran, Stephen P.
We observed the Seyfert 1 galaxy NGC 3516 with the Goddard High Resolution Spectrograph on the Hubble Space Telescope, and obtained UV spectra at a resolution of λ/Δλ ~ 20,000 in the redshifted C IV λ1549 region. The intrinsic C IV absorption in the core of the broad emission line is resolved for the first time into four distinct kinematic compone…
Ultraviolet Spectral Dating of Stars and Galaxies
Beck, T.; Bohlin, R. C.; Heap, S. R. +17 more
An echelle spectrogram (R = 30,000) of the 2300-3100 Å region in the ultraviolet spectrum of the F8 V star 9 Comae is presented. The observation is used to calibrate features in the mid-ultraviolet spectra of similar stars according to age and metal content. In particular, the spectral break at 2640 Å is interpreted using the spectral synthesis co…
The 3-D Plasma Distribution Function Analyzers With Time-of-Flight Mass Discrimination for Cluster, FAST, and Equator-S
Balsiger, H.; Klecker, B.; Kistler, L. M. +39 more
A similar time-of-flight plasma analyzer system will be flown as CODIF (COmposition and DIstribution Function analyzer) on the four Cluster spacecraft, as ESIC (Equator-S Ion Composition instrument) on Equator-S, and as TEAMS (Time-of-flight Energy Angle Mass Spectrograph) on FAST. These instruments will for the first time allow the 3-dimensional …
Hubble Space Telescope Ultraviolet Imaging and High-Resolution Spectroscopy of Water Photodissociation Products in Comet Hyakutake (C/1996 B2)
Feldman, P. D.; Keller, H. U.; Combi, M. R. +3 more
Comet Hyakutake (C/1996 B2) provided a target of opportunity for performing a systematic study of water photodissociation products in which we obtained data from three instruments on the Hubble Space Telescope (HST). The HST Goddard High Resolution Spectrograph (GHRS) was used to measure the line profile of hydrogen Lyα (H Lyα) at six locations ar…