Does heating by AGN shocks affect abundance profiles in galaxy clusters ?

作者：Xiang F^*; Rudometkin E; Churazov E; Forman W; Boehringer H

来源：Monthly Notices of the Royal Astronomical Society, 2009, 398(2): 575-582.

DOI：10.1111/j.1365-2966.2009.15139.x

• galaxies: abundances
• galaxies: clusters: general

We evaluate the impact of gas shock heating by a central active galactic nuclei (AGN) in M87 on the radial distribution of heavy elements. The propagation of a shock creates an inverted entropy profile, and the subsequent rearrangement of the gaseous atmosphere transports metal-rich gas from the central region to larger radii. We show that for the parameters of the relatively weak shock, recently found in M87, the abundance profile is not strongly affected by the redistribution of the shock heated gas (except for the very central region). At the same time, the energetics of the source is fully sufficient to broaden the metal distribution to match the observations, strongly suggesting that mechanisms other than direct shock heating must operate in cluster cores. The absence of a very strong abundance peak at the very centre of M87 suggests that the central AGN produces frequent (every few 10 Myr) and relatively weak outbursts, rather than rarer (every few 100 Myr) and an order of magnitude more powerful events.

• 出版日期2009-9-11