We present a 66 ksec Chandra X-ray observation of the galaxy cluster RXJ0334.2-0111. This deep observation revealed a unique bow shock system associated with a wide angle tail (WAT) radio galaxy and several intriguing substructures. The temperature across the bow shock jumps by a factor of ∼ 1.5 (from 4.1 keV to 6.2 keV), and is consistent with the Mach number M=1.6+0.5−0.3. A second inner surface brightness edge is a cold front that marks the border between infalling subcluster cool core and the ICM of the main cluster. The temperature across the cold front increases from 1.3+0.3−0.8 keV to 6.2+0.6−0.6 keV. We find an overpressurized region ∼ 250 kpc east of the cold front that is named "the eastern extension (EE)". The EE may be a part of the third subcluster in the ongoing merger. We also find a tail shaped feature that originates near the bow shock and may extend up to a distance of ∼ 1 Mpc. This feature is also likely overpressurized. The luminous FR-I radio galaxy, 3C89, appears to be the cD galaxy of the infalling subcluster. We estimated 3C89's jet power from jet bending and the possible interaction between the X-ray gas and the radio lobes. A comparison between the shock stand-off distance and the Mach number for all known shock front/cold front combinations suggests that the core is continuously shrinking in size by stripping.
Shocking features in the merging galaxy cluster RXJ0334.2-0111
MASSARO, Francesco;
2016-01-01
Abstract
We present a 66 ksec Chandra X-ray observation of the galaxy cluster RXJ0334.2-0111. This deep observation revealed a unique bow shock system associated with a wide angle tail (WAT) radio galaxy and several intriguing substructures. The temperature across the bow shock jumps by a factor of ∼ 1.5 (from 4.1 keV to 6.2 keV), and is consistent with the Mach number M=1.6+0.5−0.3. A second inner surface brightness edge is a cold front that marks the border between infalling subcluster cool core and the ICM of the main cluster. The temperature across the cold front increases from 1.3+0.3−0.8 keV to 6.2+0.6−0.6 keV. We find an overpressurized region ∼ 250 kpc east of the cold front that is named "the eastern extension (EE)". The EE may be a part of the third subcluster in the ongoing merger. We also find a tail shaped feature that originates near the bow shock and may extend up to a distance of ∼ 1 Mpc. This feature is also likely overpressurized. The luminous FR-I radio galaxy, 3C89, appears to be the cD galaxy of the infalling subcluster. We estimated 3C89's jet power from jet bending and the possible interaction between the X-ray gas and the radio lobes. A comparison between the shock stand-off distance and the Mach number for all known shock front/cold front combinations suggests that the core is continuously shrinking in size by stripping.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.