MACS J0553.4-3342: a young merging galaxy cluster caught through the eyes of Chandra and HST
Abstract
We present a detailed analysis of a young merging galaxy cluster MACS J0553.4-3342 (z=0.43) from Chandra X-ray and Hubble Space Telescope archival data. X-ray observations confirm that the X-ray emitting intra-cluster medium (ICM) in this system is among the hottest (average T = 12.1 ± 0.6 keV) and most luminous known. Comparison of X-ray and optical images confirms that this system hosts two merging subclusters SC1 and SC2, separated by a projected distance of about 650 kpc. The subcluster SC2 is newly identified in this work, while another subcluster (SC0), previously thought to be a part of this merging system, is shown to be possibly a foreground object. Apart from two subclusters, we find a tail-like structure in the X-ray image, extending to a projected distance of ∼1 Mpc, along the north-east direction of the eastern subcluster (SC1). From a surface brightness analysis, we detect two sharp surface brightness edges at ∼40 (∼320 kpc) and ∼80 arcsec (∼640 kpc) to the east of SC1. The inner edge appears to be associated with a merger-driven cold front, while the outer one is likely to be due to a shock front, the presence of which, ahead of the cold front, makes this dynamically disturbed cluster interesting. Nearly all the early-type galaxies belonging to the two subclusters, including their brightest cluster galaxies, are part of a well-defined red sequence.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- December 2017
- DOI:
- 10.1093/mnras/stx2028
- arXiv:
- arXiv:1701.00197
- Bibcode:
- 2017MNRAS.472.2042P
- Keywords:
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- galaxies: active;
- galaxies: clusters: individual: MACS J0553.4-3342;
- galaxies: general;
- X-rays: galaxies: clusters;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 13 pages, 12 figures, 6 Tables, Accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal