Chandra observation of the core of the galaxy cluster AWM 7.
FURUSHO T., YAMASAKI N.Y. and OHASHI T.
Abstract (from CDS):
We present results from a Chandra observation of the core region of the nearby X-ray-bright galaxy cluster AWM 7. There are bloblike substructures, which are seen in the energy band 2-10 keV, within 10 kpc (20'') of the cD galaxy NGC 1129, and the brightest subpeak has a spatial extent more than 4 kpc. We also notice that the central soft X-ray peak is slightly offset from the optical center by 1 kpc. These structures have no correlated features in optical, infrared, or radio bands. The energy spectrum of the hard subpeak indicates a temperature higher than 3 keV with a metallicity less than 0.3 solar, or a power-law spectrum with photon index ∼1.2. A hardness ratio map and a narrow Fe K band image jointly indicate two Fe-rich blobs symmetrically located around the cD galaxy, with the direction perpendicular to the subpeak direction. In larger scales (r<60 kpc), the temperature gradually drops from 4 to 2 keV toward the cluster center, and the metal abundance rises steeply to a peak of 1.5 solar at r~7 kpc. These results indicate that a dynamical process is going on in the central region of AWM 7, which probably creates heated gas blobs and drives metal injection.
Galaxies: Clusters: Individual: Alphanumeric: AWM 7 - Galaxies: Individual: NGC Number: NGC 1129 - Galaxies: Intergalactic Medium - X-Rays: Galaxies