Discovery of one of the longest X-ray tails

The interaction processes in galaxy clusters between the hot ionized gas (ICM) and the member galaxies are of crucial importance to understand the dynamics in galaxy clusters, the chemical enrichment processes, and the validity of their hydrostatic mass estimates.

Our very recent discovery of an X-ray tail in the galaxy cluster Zwicky 8338 shows for the first time a gas stripping scenario which removed completely the X-ray luminous gas from the host galaxy. Furthermore, it is one of the longest galaxy-associated X-ray tails known and exhibits an extraordinarily high luminosity. We measure an increase in metal enrichment in the center of the tail and a small temperature increase toward its outer regions. In the composite X-ray / optical image one can see the small offset between the tail and the 14th magnitude galaxy. Radio counterparts support (with low significance) the idea of an infalling galaxy which interacts with the galaxy cluster ICM. 


Thomas Reiprich

Argelander-Institut für Astronomie
Auf dem Hügel 71
D-53121 Bonn

+49 228 73 - 3642