Oral Abstract

Oral Contribution (O0.6) Xiaoyuan Zhang (Leiden University / SRON)

Deep Chandra observations of double relic cluster ZwCl 2341+0000

We present the results of deep Chandra observations of ZwCl 2341+0000, which is a merging galaxy cluster hosting double radio relics. Previous study shows that half of the southern relic is associated with an X-ray surface brightness discontinuity while the other half not. The discontinuity was believed to be a shock front. Therefore it is a mysterious case of an only partial shock-relic connection. By using the 206.5 ks deep Chandra observations, we find that the previously reported southern surface brightness discontinuity is identified as a cold front based on the new temperature measurements. The actual location of the southern shock front is at the southeastern edge of the southern relic, which is unveiled by the radio spectral index map calculated using new GMRT 325 MHz and JVLA 1.5 GHz images. Meanwhile, the deep observations also serendipitously reveal several intriguing features, such as a unique cone shaped northern subcluster, a 400 kpc straight gas trail stripped from the cone apex, a peculiar high temperature region between the two subclusters that doesn't hold pressure equilibrium with the ambient gas. The northern subcluster is in a perfect cone shape, with a 500 kpc long cold front on each side. This type of conic subcluster has been predicted by simulations but is observed here for the first time. It represents a transition stage between a blunt body cold front and a slingshot cold front. The new findings improve the knowledge of the evolution of remnant core in head-on mergers.