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Radio Observations of the Hubble Deep Field-South Region. II. The 1.4 GHz Catalog and Source Counts
Norris, Ray P.; Huynh, Minh T.; Jackson, Carole A. +1 more
This paper is part of a series describing the results from the Australia Telescope Hubble Deep Field-South (ATHDFS) survey obtained with the Australia Telescope Compact Array. This survey consists of observations at 1.4, 2.5, 5.2, and 8.7 GHz, all centered on the Hubble Deep Field-South. Here we present the first results from the extended observin…
Hubble Space Telescope WFPC2 Color-Magnitude Diagrams for Globular Clusters in M31
Djorgovski, S. G.; Cacciari, C.; Rich, R. M. +4 more
We report new photometry for 10 globular clusters in M31, observed to a uniform depth of four orbits in F555W (V) and F814W (I) using WFPC2 on board the Hubble Space Telescope (HST). In addition, we have reanalyzed HST archival data of comparable quality for two more clusters. A special feature of our analysis is the extraordinary care taken to ac…
Proper Motions of Dwarf Spheroidal Galaxies from Hubble Space Telescope Imaging. III. Measurement for Ursa Minor
Minniti, Dante; Mateo, Mario; Piatek, Slawomir +5 more
This article presents a measurement of the proper motion of the Ursa Minor dwarf spheroidal galaxy determined from images taken with the Hubble Space Telescope in two distinct fields. Each field contains a quasi-stellar object that serves as the ``reference point.'' The measured proper motion for Ursa Minor, expressed in the equatorial coordinate …
Feeding the Monster: The Nucleus of NGC 1097 at Subarcsecond Scales in the Infrared with the Very Large Telescope
Reunanen, Juha; Prieto, M. Almudena; Maciejewski, Witold
Near-IR images of the prototype LINER/Seyfert type 1 galaxy NGC 1097 observed with the Very Large Telescope using adaptive optics disclose with unprecedented detail a complex central network of filamentary structure spiraling down to the center of the galaxy. The structure, consisting of several spiral arms, some almost completing a revolution abo…
The NGC 5846 Group: Dynamics and the Luminosity Function to MR=-12
Mahdavi, Andisheh; Tully, R. Brent; Trentham, Neil
We conduct a photometric and spectroscopic survey of a 10 deg2 region surrounding the nearby NGC 5846 group of galaxies, using the Canada-France-Hawaii and Keck I telescopes to study the population of dwarf galaxies as faint as MR=-10. Candidates are identified on the basis of quantitative surface brightness and qualitative m…
An Analysis of the Shapes of Ultraviolet Extinction Curves. IV. Extinction without Standards
Fitzpatrick, E. L.; Massa, D.
In this paper we present a new method for deriving UV through IR extinction curves, based on the use of stellar atmosphere models to provide estimates of the intrinsic (i.e., unreddened) stellar spectral energy distributions (SEDs), rather than unreddened (or lightly reddened) standard stars. We show that this ``extinction without standards'' tech…
A Study of Edge-On Galaxies with the Hubble Space Telescope Advanced Camera for Surveys. I. Initial Results
de Jong, Roelof S.; Seth, Anil C.; Dalcanton, Julianne J.
We present the initial results of a Hubble Space Telescope/Advanced Camera for Surveys snapshot survey of 16 nearby, edge-on, late-type galaxies covering a range in distance from 2 to 19 Mpc. The images of these galaxies show significant resolved stellar populations. We derive F606W and F814W photometry for more than 1.2 million stars and present …
High-Resolution, Long-Slit Spectroscopy of VY Canis Majoris: The Evidence for Localized High Mass Loss Events
Humphreys, Roberta M.; Davidson, Kris; Wallerstein, George +1 more
High spatial and spectral resolution spectroscopy of the OH/IR supergiant VY CMa and its circumstellar ejecta reveals evidence for high mass loss events from localized regions on the star occurring over the past 1000 yr. The reflected absorption lines and the extremely strong K I emission lines show a complex pattern of velocities in the ejecta. W…
X-Ray Properties of Lyman Break Galaxies in the Great Observatories Origins Deep Survey
Lehmer, B. D.; Alexander, D. M.; Giavalisco, M. +9 more
We constrain the X-ray emission properties of Lyman break galaxies (LBGs) at z~3-6 using the ~2 Ms Chandra Deep Field North and ~1 Ms Chandra Deep Field South. Large samples of LBGs were discovered using the Hubble Space Telescope as part of the Great Observatories Origins Deep Survey (GOODS). Deep optical and X-ray imaging over the GOODS fields h…
The Loopy Ultraviolet Line Profiles of RU Lupi: Accretion, Outflows, and Fluorescence
Herczeg, Gregory J.; Valenti, Jeff A.; Brown, Alexander +6 more
We present far-ultraviolet (FUV) spectra of the classical T Tauri star RU Lup covering the 912-1710 Å spectral range, as observed by the Hubble Space Telescope STIS and the Far Ultraviolet Spectroscopic Explorer satellite. We use these spectra, which are rich in emission and absorption lines, to probe both the accreting and outflowing gas. Absorpt…