2019/07/24 by Gerrit Schellenberger, Laurence P. David, Ewan O'Sullivan +2 · 1 voice
Physics and Astronomy · #astro-ph.GA #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/ab35e4
accepted by ApJ, 24 pages, 16 figures
arxiv created 2019/07/24 · arxiv published 2019/07/24 · arxiv updated 2019/09/11
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.