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Abstract: Aims. We investigate whether X-ray observations map heavy elements in theIntra-Cluster Medium ICM well and whether the X-ray observations yield goodestimates for the metal mass, with respect to predictions on transport mech-anisms of heavy elements from galaxies into the ICM. We further test theaccuracy of simulated metallicity maps. Methods. We extract synthetic X-rayspectra from N-body-hydrodynamic simulations including metal enrichment pro-cesses, which we then analyse with the same methods as are applied toobservations. By changing the metal distribution in the simulated galaxyclusters, we investigate the dependence of the overall metallicity as afunction of the metal distribution. In addition we investigate the differenceof X-ray weighted metal maps produced by simulations and metal maps extractedfrom artifcial X-ray spectra, which we calculate with SPEX2.0 and analyse withXSPEC12.0. Results. The overall metallicity depends strongly on thedistribution of metals within the galaxy cluster. The more inhomogeneously themetals are distributed within the cluster, the less accurate is the metallicityas a measure for the true metal mass. The true metal mass is generallyunderestimated by X-ray observations. The difference between the X-ray weightedmetal maps and the metal maps from synthetic X-ray spectra is on average lessthan 7% in the temperature regime above T > 3E7 K, i.e. X-ray weighted metalmaps can be well used for comparison with observed metal maps. Extracting themetal mass in the central parts r < 500 kpc of galaxy clusters with X-rayobservations results in metal mass underestimates up to a factor of three.



Autor: W. Kapferer 1, T. Kronberger 1, J. Weratschnig 1, S. Schindler 1 1 Institut fuer Astro- und Teilchenphysik, Universitaet Innsbruc

Fuente: https://arxiv.org/







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