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XMM-Newton and Chandra Observations of the Galaxy Group NGC 5044. II. Metal Abundances and Supernova Fraction
Buote, David A.; Brighenti, Fabrizio; Mathews, William G. +1 more
Using new XMM and Chandra observations, we present an analysis of the metal abundances of the hot gas within a radius of 100 kpc of the bright nearby galaxy group NGC 5044. Motivated by the inconsistent abundance and temperature determinations obtained by different observers for X-ray groups, we provide a detailed investigation of the systematic e…
The Slow Temperature Equilibration behind the Shock Front of SN 1006
Vink, Jacco; Kaastra, Jelle S.; Laming, J. Martin +2 more
We report on the observation of O VII Doppler line broadening in a compact knot at the edge of SN 1006 detected with the reflective grating spectrometer on board XMM-Newton. The observed line width of σ=3.4+/-0.5 eV at a line energy of 574 eV indicates an oxygen temperature of kT=528+/-150 keV. Combined with the observed electron temperature of ~1…
Constraints on Coronal Mass Ejection Dynamics from Simultaneous Radio and White-Light Observations
Burkepile, J. T.; Kaiser, M. L.; Howard, R. A. +5 more
Simultaneous radio and white-light observations are used to deduce information on the dynamics of two coronal mass ejection (CME) events that occurred about 2 hr apart on 2001 January 20 and that were associated with eruptions from the same active region on the Sun. The analysis combines both space-based and ground-based data. The radio data were …
Can a Dusty Warm Absorber Model Reproduce the Soft X-Ray Spectra of MCG -6-30-15 and Markarian 766?
Kahn, Steven M.; Paerels, Frits; Behar, Ehud +8 more
XMM-Newton RGS spectra of MCG -6-30-15 and Mrk 766 exhibit complex discrete structure, which was interpreted in a paper by Branduardi-Raymont and coworkers as evidence for the existence of relativistically broadened Lyα emission from carbon, nitrogen, and oxygen, produced in the innermost regions of an accretion disk around a Kerr black hole. This…
Resolved Mid-Infrared Emission in the Narrow-Line Region of NGC 4151
Robinson, A.; De Buizer, James M.; Radomski, James T. +4 more
We present subarcsecond-resolution mid-infrared images of NGC 4151 at 10.8 and 18.2 µm. These images were taken with the University of Florida mid-IR camera/spectrometer OSCIR at the Gemini North 8 m telescope. We resolve emission at both 10.8 and 18.2 µm, extending ~3.5" across at a P.A. of ~60°. This coincides with the narrow-line re…
The Puzzling Dynamical Status of the Core of the Globular Cluster NGC 6752
Sabbi, E.; Possenti, A.; Origlia, L. +4 more
We have used high-resolution Hubble Space Telescope Wide Field Planetary Camera 2 and ground-based wide-field images to determine the center of gravity and construct an extended radial density and brightness profile of the cluster NGC 6752 including, for the first time, detailed star counts in the very inner region. The barycenter of the nine inne…
The First Deep Advanced Camera for Surveys Lyα Images of Local Starburst Galaxies
Östlin, Göran; Leitherer, Claus; Mas-Hesse, J. Miguel +2 more
We report the first results from a deep Lyα imaging program of local starburst galaxies with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The two observed galaxies ESO 350-IG038 and SBS 0335-052 have luminosities similar to those of the Magellanic Clouds but differ in their chemical composition. ESO 350-IG038 has an oxygen …
XMM-Newton and Chandra Observations of the Galaxy Group NGC 5044. I. Evidence for Limited Multiphase Hot Gas
Buote, David A.; Brighenti, Fabrizio; Mathews, William G. +1 more
Using new XMM and Chandra observations, we present an analysis of the temperature structure of the hot gas within a radius of 100 kpc of the bright nearby galaxy group NGC 5044. A spectral deprojection analysis of data extracted from circular annuli reveals that a two-temperature model (2T) of the hot gas is favored over single-phase or cooling fl…
A Hubble Space Telescope Wide Field Planetary Camera 2 Survey for Brown Dwarf Binaries in the α Persei and Pleiades Open Clusters
Bouy, Hervé; Barrado y Navascués, David; Martín, Eduardo L. +2 more
We present the results of a high-resolution imaging survey for brown dwarf binaries in two open clusters. The observations were carried out with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. Our sample consists of eight brown dwarf candidates in α Persei and 25 brown dwarf candidates in the Pleiades. We have resolved four …
Age Dependence of the Vega Phenomenon: Observations
Waters, L. B. F. M.; Dominik, C.; Waelkens, C. +1 more
We study the time dependency of Vega-like excesses using infrared studies obtained with the imaging photopolarimeter ISOPHOT on board the Infrared Space Observatory. We review the different studies published on this issue and critically check and revise ages and fractional luminosities in the different samples. The conclusions of our study differ …