Journal Article

Gas sloshing, cold fronts, Kelvin–Helmholtz instabilities and the merger history of the cluster of galaxies Abell 496

E. Roediger, L. Lovisari, R. Dupke, S. Ghizzardi, M. Brüggen, R. P. Kraft and M. E. Machacek

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 420, issue 4, pages 3632-3648
Published in print March 2012 | ISSN: 0035-8711
Published online March 2012 | e-ISSN: 1365-2966 | DOI: https://dx.doi.org/10.1111/j.1365-2966.2011.20287.x
Gas sloshing, cold fronts, Kelvin–Helmholtz instabilities and the merger history of the cluster of galaxies Abell 496

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics

GO

Show Summary Details

Preview

We investigate the origin and nature of the multiple sloshing cold fronts in the core of Abell 496 by direct comparison between observations and dedicated hydrodynamical simulations. Our simulations model a minor merger with a 4 × 1013 M subcluster crossing A496 from the south-west to the north–north-east, passing the cluster core in the south-east at a pericentre distance of 100 to a few × 100 kpc about 0.6–0.8 Gyr ago. The gas sloshing triggered by the merger can reproduce almost all observed features, e.g. the characteristic spiral-like brightness residual distribution in the cluster centre and its asymmetry out to 500 kpc, also the positions of and contrasts across the cold fronts. If the subcluster passes close (100 kpc) to the cluster core, the resulting shear flows are strong enough to trigger Kelvin–Helmholtz instabilities that in projection resemble the peculiar kinks in the cold fronts of Abell 496. Finally, we show that sloshing does not lead to a significant modification of the global intracluster medium profiles but a mild oscillation around the initial profiles.

Keywords: methods: numerical; galaxies: clusters: individual: A496; galaxies: clusters: intracluster medium; X-rays: galaxies: clusters

Journal Article.  11227 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.