The Intracluster Medium in z>1 Galaxy Clusters
Abstract
The Chandra X-Ray Observatory was used to obtain a 190 ks image of three high-redshift galaxy clusters in one observation. The results of our analysis of these data are reported for the two z>1 clusters in this Lynx field, which are the most distant known X-ray luminous clusters. Spatially extended X-ray emission was detected from both these clusters, indicating the presence of hot gas in their intracluster media. A fit to the X-ray spectrum of RX J0849+4452 at z=1.26 yields a temperature of kT=5.8+2.8-1.7 keV. Using this temperature and the assumption of an isothermal sphere, the total mass of RX J0849+4452 is found to be 4.0+2.4-1.9×1014 h-165 Msolar within r=1 h-165 Mpc. The TX for RX J0849+4452 approximately agrees with the expectation based on its Lbol=3.3+0.9-0.5×1044 ergs s-1 according to the low-redshift LX-TX relation. The very different distributions of X-ray-emitting gas and of the red member galaxies in the two z>1 clusters, in contrast to the similarity of the optical/IR colors of those galaxies, suggests that the early-type galaxies mostly formed before their host clusters.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 2001
- DOI:
- 10.1086/320583
- arXiv:
- arXiv:astro-ph/0012250
- Bibcode:
- 2001ApJ...552..504S
- Keywords:
-
- Galaxies: Clusters: General;
- X-Rays: General;
- Astrophysics
- E-Print:
- 4 pages in emulateapj style plus 2 color jpegs for Figure 3. Accepted by The Astrophysical Journal