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Abundances and chemical stratification analysis in the atmosphere of Cr-type Ap star HD 204411
Ryabchikova, T.; Leone, F.; Kochukhov, O.
We present results of an abundance and stratification analysis of the weakly magnetic chemically peculiar star HD 204411 based on the echelle spectrum obtained with the high resolution spectrograph at the 3.55-m Telescopio Nazionale Galileo at the Observatorio del Roque de los Muchachos (La Palma, Spain). Atmospheric parameters obtained from the s…
RX J0152.7-1357: Stellar Populations in an X-Ray Luminous Galaxy Cluster at z = 0.83
Crampton, David; Jørgensen, Inger; Takamiya, Marianne +3 more
We present a study of the stellar populations of galaxies in the cluster RX J0152.7-1357 at a redshift of 0.83. The study is based on new high signal-to-noise ratio spectroscopy of 29 cluster members covering the wavelength range 5000-10000 Å, as well as r'i'z' photometry of the cluster. We use scaling relations be…
Far-Infrared Observations of Radio Quasars and FR II Radio Galaxies
Egami, E.; Gordon, K. D.; Rieke, G. H. +6 more
We report MIPS photometry of 20 radio-loud quasars and galaxies at 24 and 70 µm (and of five at 160 µm). We combine this sample with additional sources detected in the far-infrared by IRAS and ISO for a total of 47 objects, including 23 steep-spectrum type I AGNs: radio-loud quasars and broad-line radio galaxies; and 24 type II AGNs: n…
Coronagraphic Imaging of Pre-Main-Sequence Stars with the Hubble Space Telescope Space Telescope Imaging Spectrograph. I. The Herbig Ae Stars
Roberge, A.; Gull, T. R.; Sitko, M. L. +10 more
STIS white-light coronagraphic imaging has been carried out for 14 nearby, lightly reddened Herbig Ae stars, providing data on the environments and disks associated with these stars. No disks are detected in our data when the Herbig Ae star is accompanied by a stellar companion at r<=2''. We find that the optical visibility of protop…
SDSS J042348.57-041403.5AB: A Brown Dwarf Binary Straddling the L/T Transition
Burrows, Adam; Kirkpatrick, J. Davy; Burgasser, Adam J. +3 more
We present the discovery of SDSS J042348.57-041403.5 as a closely separated (0.16") brown dwarf binary, resolved by the Hubble Space Telescope Near-Infrared Camera and Multi-Object Spectrometer. Physical association is deduced from the angular proximity of the components and constraints on their common proper motion. SDSS 0423-0414AB appears to be…
The 1st INTEGRAL SPI-ACS gamma-ray burst catalogue
Hurley, K.; Rau, A.; Lichti, G. G. +1 more
We present the sample of gamma-ray bursts detected with the anti-coincidence shield ACS of the spectrometer SPI on-board INTEGRAL for the first 26.5 months of mission operation (up to Jan. 2005). SPI-ACS works as a nearly omnidirectional gamma-ray burst detector above ~80 keV but lacks spatial and spectral information. In this catalogue, the prope…
The Metallicity Distribution Function of Field Stars in M31's Bulge
Sarajedini, Ata; Jablonka, Pascale
We have used Hubble Space Telescope Wide Field Planetary Camera 2 observations to construct a color-magnitude diagram (CMD) for the bulge of M31 at a location ~1.6 kpc from the galaxy's center. Using scaled solar abundance theoretical red giant branches with a range of metallicities, we have translated the observed colors of the stars in the CMD t…
The opposition surge of Enceladus: HST observations 338-1022 nm
French, Richard G.; Verbiscer, Anne J.; McGhee, Colleen A.
Hubble Space Telescope (HST) Wide-Field Planetary Camera (WFPC2) observations at phase angles in the range α=0.26°-6.4° obtained at every opposition and near quadrature between October 1996 and December 2002 reveal the opposition effect of Enceladus. We present a photometric analysis of nearly 200 images obtained through the five broadband UVBRI f…
An Ultracompact X-Ray Binary in the Globular Cluster M15 (NGC 7078)
Knigge, C.; Charles, P. A.; Long, K. S. +5 more
We have used the Advanced Camera for Surveys on board the Hubble Space Telescope to image the core of the globular cluster M15 in the far-ultraviolet (FUV) wave band. Based on these observations, we identify the FUV counterpart of the recently discovered low-mass X-ray binary M15 X-2. Our time-resolved FUV photometry shows a modulation with 0.062+…
Rotationally Resolved 8-35 Micron Spitzer Space Telescope Observations of the Nucleus of Comet 9P/Tempel 1
A'Hearn, M. F.; Groussin, O.; Charmandaris, V. +6 more
We have utilized the Spitzer Space Telescope (SST) Infrared Spectrograph (IRS) to directly observe thermal emission from the nucleus of comet 9P/Tempel 1 on UT 2004 March 25-27. We obtained 8-35 µm low-resolution (R~100) spectra and contemporaneous 16 and 22 µm photometric imaging over a 39 hr period. The comet was 3.7 AU from the Sun …