Velocity Gradients in the Intracluster Gas of the Perseus Cluster
Abstract
We report the results of spatially resolved X-ray spectroscopy of eight different ASCA pointings distributed symmetrically around the center of the Perseus Cluster. The outer region of the intracluster gas is roughly isothermal, with temperature ~6-7 keV and metal abundance ~0.3 solar. Spectral analysis of the central pointing is consistent with the presence of a cooling flow and a central metal abundance gradient. A significant velocity gradient is found along an axis at a position angle of ~135°, which is ~45° discrepant with the major axis of the X-ray elongation. The radial velocity difference is found to be greater than 1000 km s-1 Mpc-1 at the 90% confidence level. Simultaneous fittings of GIS 2 and 3 indicate that the velocity gradient is significant at the 95% confidence level, and the F-test rules out constant velocities at the 99% level. Intrinsic short- and long-term variations of gain are unlikely (P<0.03) to explain the velocity discrepancies.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 2001
- DOI:
- 10.1086/318393
- arXiv:
- arXiv:astro-ph/0009429
- Bibcode:
- 2001ApJ...547..705D
- Keywords:
-
- Galaxies: Cooling Flows;
- Galaxies: Clusters: Individual: Name: Abell 426;
- Galaxies: Intergalactic Medium;
- X-Rays: Galaxies;
- Astrophysics
- E-Print:
- 19 pages, 6 figures, accepted for publication in the Astrophysical Journal