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Active Region Transient Events Observed with TRACE
Reeves, Katharine K.; Golub, Leon; Winebarger, Amy R. +3 more
Nearly all active region observations made by the Transition Region and Coronal Explorer (TRACE) contain seemingly spontaneous, short-lived brightenings in small-scale loops. In this paper, we present an analysis of these brightenings using high-cadence TRACE observations of Active Region 9506 on 2001 June 21 from 15:17:00 to 15:46:00 UT. During t…
Extreme Ultraviolet Explorer Observations of λ Andromedae
Sanz-Forcada, J.; Dupree, A. K.; Brickhouse, N. S.
Extreme-ultraviolet spectra (70-740 Å) and light curves (75-175 Å) of the spectroscopic binary system λ Andromedae (HD 222107) were obtained with the Extreme Ultraviolet Explorer (EUVE) satellite in 1997 July and August. Two flares were detected during the observations that spanned 15 days, or almost 3/4 of the orbital period of 20.5 days, with a …
Hot Outflowing Gas from the X-Ray Binary Hercules X-1
Boroson, Bram; Kallman, Timothy; Vrtilek, Saeqa Dil
We present a unified picture of outflowing gas from the X-ray binary system Hercules X-1/HZ Herculis. We suggest that the outflowing gas (a wind) causes UV emission seen in mid-eclipse, narrow UV absorption lines, and broad UV P Cygni lines. Observations with the FOS and STIS spectrographs on the Hubble Space Telescope (HST) show UV emission lines…
Connecting the Sun and the Solar Wind: Comparison of the Latitudinal Profiles of Coronal and Ulysses Measurements of the Fast Wind
Habbal, Shadia Rifai; Woo, Richard
A quantitative comparison of the latitudinal profile of polarized brightness (pB) measurements nearest the Sun at 1.15 Rsolar by the Mauna Loa Solar Observatory K-Coronameter and Ulysses interplanetary measurements of the fast solar wind during its first south polar pass, at the declining phase of the solar cycle, is made for the first …
Long-Slit Observations of Extended C II λ1335 Emission around V854 Centauri and RY Sagittarii
Clayton, G. C.; Ayres, T. R.
We have obtained long-slit far-ultraviolet (1150-1730 Å) spectra of the R Coronae Borealis (RCB) stars V854 Cen and RY Sgr near maximum light and pulsational phase zero with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. The far-UV spectrum of each star shows a photospheric continuum rising steeply toward longer wave…
Stellar Variability in the Metal-rich, Obscured Globular Cluster Terzan 5
Edmonds, Peter D.; Grindlay, Jonathan E.; Cohn, Haldan +1 more
We present the results of a search for variability in and near the core of the metal-rich, obscured globular cluster Terzan 5, using the near-infrared camera and multiobject spectrometer (NICMOS) on board the Hubble Space Telescope. This extreme cluster has approximately solar metallicity and a central density that places it in the upper few perce…
WFPC2 Imaging of Quasar Environments: A Comparison of Large Bright Quasar Survey and Hubble Space Telescope Archive Quasars
Hooper, Eric J.; Impey, Chris D.; Finn, Rose A.
We present Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) data on the large-scale environments of 16 0.39<z<0.51 quasars from the Large Bright Quasar Survey (LBQS). The LBQS quasars are representative of the radio-quiet population, and this is one of the first looks at their large-scale environments. We compare the LBQS e…
The Extreme-Ultraviolet Structure and Properties of a Newly Emerged Active Region
Gallagher, Peter T.; Phillips, Kenneth J. H.; Lee, Jeongwoo +2 more
The structure and properties of a newly emerged solar active region (NOAA Active Region 7985) are discussed using the Coronal Diagnostic Spectrometer (CDS) and the Extreme-Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory. CDS obtained high-resolution EUV spectra in the 308-381 Å and 513-633 Å wavelength ranges, w…
Ultraviolet Broad Absorption Features and the Spectral Energy Distribution of the Quasar PG 1351+64
Zheng, W.; Kriss, G. A.; Wang, J. X. +7 more
We present a moderate-resolution (~20 km s-1) spectrum of the mini-broad absorption line quasar (QSO) PG 1351+64 between 915 and 1180 Å, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE). Additional low-resolution spectra at longer wavelengths were also obtained with the Hubble Space Telescope (HST) and ground-based telesc…
Evidence for a Very Young Age of F Stars with Extrasolar Planets
Schultz, A. B.; Suchkov, A. A.
We assess the age of nine planet-bearing (PB) F stars by comparing their metallicity, Hp variability, brightness anomaly, and location in the color-magnitude diagram with the same parameters for the Hyades and field F stars. Combined evidence from these parameters suggests that the age of our PB F stars is not very much different from the age of t…