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arXiv · 1907.10581

Forming one of the most massive objects in the Universe: The quadruple merger in Abell 1758

Gerrit Schellenberger·Laurence P. David·Ewan O'Sullivan·Jan M. Vrtilek·Chris P. Haines
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Abstract

Abell1758 is a system of two galaxy clusters, a more massive, northern cluster and a southern cluster. Both parts are undergoing major merger events at different stages. Although the mass of the merger constituents provides enough energy to produce visible shock fronts in the X-ray, none have been found to date. We present detailed temperature and abundance maps based on Chandra ACIS data, and identify several candidates for shocks and cold fronts from a smoothed gradient map of the surface brightness. One candidate can be confirmed as the missing shock front in the northern cluster through X-ray spectroscopy. Non-thermal radio emission observed with the GMRT confirms the presence of radio halos in the northern and southern clusters, and shows evidence for a relic in the periphery of the southern cluster. We do not find evidence for shocked gas between A1758N and A1758S.

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Gerrit Schellenberger, Laurence P. David, Ewan O'Sullivan, Jan M. Vrtilek, Chris P. Haines. 2019-07-24. Forming one of the most massive objects in the Universe: The quadruple merger in Abell 1758. https://doi.org/10.3847/1538-4357%2Fab35e4

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