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arXiv · 1306.1241

Metal jumps across sloshing cold fronts: the case of A496

Simona Ghizzardi·Sabrina De Grandi·Silvano Molendi
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Abstract

Cold-fronts in cool-core clusters are thought to be induced by minor mergers and to develop through a sloshing mechanism. While temperature and surface-brightness jumps have been detected and measured in many systems, a detailed characterization of the metal abundance across the discontinuity is only available for a handful of objects. Within the sloshing scenario, we expect the central cool and metal rich gas to be displaced outwards into lower abundance regions, thus generating a metal discontinuity across the front. We analyzed a long (120 ksec) XMM-Newton observation of A496 to study the metal distribution and its correlation with the cold-fronts. We find Fe discontinuities across the two main cold-fronts located ~60 kpc NNW and ~160 kpc South of the peak and a metal excess in the South direction.

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Simona Ghizzardi, Sabrina De Grandi, Silvano Molendi. 2013-06-05. Metal jumps across sloshing cold fronts: the case of A496. https://doi.org/10.1002/asna.201211871

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