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The Canada-UK Deep Submillimeter Survey. VI. The 3 Hour Field
Ivison, R. J.; Clements, D. L.; Dunne, L. +6 more
We present the complete submillimeter data for the Canada-UK Deep Submillimeter Survey (CUDSS) 3h field. The observations were taken with the Submillimeter Common-User Bolometric Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT) on Mauna Kea. The 3h field is one of two main fields in our survey and covers 60 arcmin
Anomalous Ultraviolet Line Flux Ratios in the Cataclysmic Variables 1RXS J232953.9+062814, CE 315, BZ Ursae Majoris, and EY Cygni, Observed with the Hubble Space Telescope Space Telescope Imaging Spectrograph
Szkody, Paula; Sion, Edward M.; Hubeny, Ivan +6 more
Brief Hubble Space Telescope Space Telescope Imaging Spectrograph spectroscopic snapshot exposures of the cataclysmic variables 1RXS J232953.9+062814, CE 315, BZ UMa, and EY Cyg reveal very large N V/C IV line flux ratios, similar to those observed in AE Aqr. Such anomalous line flux ratios have so far been observed in 10 systems and presumably re…
The DEEP Groth Strip Survey. VII. The Metallicity of Field Galaxies at 0.26 < z < 0.82 and the Evolution of the Luminosity-Metallicity Relation
Kobulnicky, Henry A.; Weiner, Benjamin J.; Faber, S. M. +6 more
Using spectroscopic data from the Deep Extragalactic Evolutionary Probe Groth Strip Survey (DGSS), we analyze the gas-phase oxygen abundances in the warm ionized medium for 64 emission-line field galaxies in the redshift range 0.26<z<0.82. These galaxies comprise a small subset selected from among 693 objects in the DGSS. They are chosen for…
The Nature of Damped Lyα Absorbing Galaxies at z <= 1: A Photometric Redshift Survey of Damped Lyα Absorbers
Chen, Hsiao-Wen; Lanzetta, Kenneth M.
We study the nature of damped Lyα absorption (DLA) systems at z<=1 using a sample of 11 DLA galaxies, for which accurate redshift measurements are available. Five of the 11 systems are identified in our ongoing photometric redshift survey of DLA galaxies, while the remaining six systems are identified by previous groups using either spectroscop…
CO (J=7-->6) Observations of NGC 253: Cosmic-Ray-heated Warm Molecular Gas
Bolatto, A. D.; Stacey, G. J.; Bradford, C. M. +5 more
We report observations of the CO J=7-->6 transition toward the starburst nucleus of NGC 253. This is the highest excitation CO measurement in this source to date and allows an estimate of the molecular gas excitation conditions. Comparison of the CO line intensities with a large velocity gradient, escape probability model indicates that the bul…
Flaring X-Ray Emission from HST-1, a Knot in the M87 Jet
Sparks, W. B.; Wilson, A. S.; Harris, D. E. +3 more
We present Chandra X-ray monitoring of the M87 jet in 2002, which shows that the intensity of HST-1, an optical knot 0.8" from the core, increased by a factor of 2 in 116 days and a factor of 4 in 2 yr. There was also a significant flux decrease over 2 months, with suggestive evidence for a softening of the spectrum. From this variability behavior…
Study of Ribbon Separation of a Flare Associated with a Quiescent Filament Eruption
Zhang, Hongqi; Qiu, Jiong; Jing, Ju +1 more
In this paper, we present a detailed study of a two-ribbon flare in the plage region observed by Kanzelhohe Solar Observatory (KSO), which is one of the stations in our global Hα network. We select this event due to its very clear filament eruption, two-ribbon separation, and association with a fast coronal mass ejection (CME). We study the separa…
A New X-Ray Flare from the Galactic Nucleus Detected with the XMM-Newton Photon Imaging Cameras
Goldoni, P.; Decourchelle, A.; Warwick, R. S. +5 more
Sgr A*, the compact radio source believed to be the counterpart of the massive black hole at the Galactic nucleus, was observed to undergo rapid and intense flaring activity in X-rays with Chandra in 2000 October. We report here the detection with XMM-Newton European Photon Imaging Cameras of the early phase of a similar X-ray flare from this sour…
Thermal X-Ray Emission from Shocked Ejecta in Type Ia Supernova Remnants: Prospects for Explosion Mechanism Identification
Badenes, Carles; Borkowski, Kazimierz J.; Bravo, Eduardo +1 more
The explosion mechanism behind Type Ia supernovae is a matter of continuing debate. The diverse attempts to identify or at least constrain the physical processes involved in the explosion have been only partially successful so far. In this paper we propose to use the thermal X-ray emission from young supernova remnants (SNRs) originating in Type I…
Tracing the Warm-Hot Intergalactic Medium at Low Redshift: X-Ray Forest Observations toward H1821+643
Mathur, Smita; Weinberg, David H.; Chen, Xuelei
We present a high-resolution (λ/Δλ~500) X-ray spectrum of the bright quasar H1821+643 (z=0.297), obtained in a 470 ks observation with the Chandra X-Ray Observatory. We search for X-ray absorption by highly ionized metal species, O VII and O VIII in particular, at the redshifts of the six intervening O VI absorption systems known from UV studies. …