Chemical enrichment in the cluster of galaxies Hydra A - AstrophysicsReport as inadecuate

Chemical enrichment in the cluster of galaxies Hydra A - Astrophysics - Download this document for free, or read online. Document in PDF available to download.

Abstract: We analyzed global properties, radial profiles and 2D maps of the metalabundances and temperature in the cool core cluster of galaxies Hydra A using adeep XMM-Newton exposure. The best fit among the available spectral models isprovided by a Gaussian distribution of the emission measure gdem. We canaccurately determine abundances for 7 elements in the cluster core with EPICand 3 elements with RGS. The gdem model gives lower Fe abundances than a singletemperature model. The abundance profiles for Fe, Si, S, but also O arecentrally peaked. Combining the Hydra A results with 5 other clusters for whichdetailed chemical abundance studies are available, we find a significantdecrease of O with radius, while the increase in the O-Fe ratio with radius issmall within 0.1 r 200. We compare the observed abundance ratios with themixing of various supernova type Ia and core-collapse yield models in differentrelative amounts. Producing the estimated O, Si and S peaks in Hydra A requireseither an amount of metals ejected by stellar winds 3-8 times higher thanpredicted by available models or a remaining peak in the enrichment bycore-collapse supernovae from the protocluster phase. The temperature map showscooler gas extending in arm-like structures towards the north and south. Thesestructures appear to be richer in metals than the ambient medium and spatiallycorrelated with the large-scale radio lobes. We estimate the mass of cool gas,which was probably uplifted by buoyant bubbles of relativistic plasma producedby the AGN, to 1.6-6.1x10^9 M sun, and the energy associated with this upliftto 3.3-12.5x10^58 ergs. The best estimate of the mass of Fe uplifted togetherwith the cool gas is 1.7x10^7 M sun, 15% of the total mass of Fe in the central0.5arcmin region.

Author: A. Simionescu, N. Werner, H. Böhringer, J.S. Kaastra, A. Finoguenov, M. Brüggen, P.E.J. Nulsen



Related documents