Extreme AGN Feedback and Cool Core Destruction in the X-ray Luminous Galaxy Cluster MACS J1931.8-2634

We report on a deep, multiwavelength study of the galaxy cluster MACS J1931.8-2634 us- ing Chandra X-ray, Subaru optical, and VLA 1.4 GHz radio data. This cluster (z = 0: 352) harbors one of the most X-ray luminous cool cores yet discovered, with an equivalent mass cooling rate within the central 50h −1 70 kpc is� 700 Myr −1 . Unique features observed in the central core of MACS J1931.8-2634 hint to a wealth of past activity that has greatly disrupted the original cool core. The X-ray and optical data suggest oscillatory motion of the cool core along a roughly north-south direction. We also observe a spiral of relatively cool, dense, X-ray emitting gas connected to the cool core, as well as highly elongated intracluster light (ICL) surrounding the cD galaxy. For a cluster with such a high nominal cooling rate, this cluster is missing the central metallicity peak almost always seen in cool core clusters, which suggests bulk transport of cool gas out to large distances from the center. Extended radio emission is observed surrounding the central AGN, elongated in the east-west direction, spatially coin- cident with X-ray cavities. The power input required to infla te these 'bubbles' is estimated from both the X-ray and radio emission to reside between Pjet� 4 - 14� 10 45 erg s −1 , putting it among the most powerful jets ever observed. This combination of a powerful AGN out- burst and bulk motion of the cool core have resulted in two X-ray bright ridges to form to the north and south of the central AGN at a distance of approximately 25 kpc. The north- ern ridge has spectral characteristics typical of cool core s: it contains low temperature, high density, metal rich gas and is consistent with being a remnant of the cool core after it was dis- rupted by the AGN and bulk motions. It is also the site of Hfilaments and young stars. The X-ray spectroscopic cooling rate associated with this ridg e is� 165 Myr −1 , which agrees with the estimate of the star formation rate from broad-band optical imaging (� 170 Myr −1 ). MACS J1931.8-2634 appears to harbor one of most profoundly disrupted low entropy cores observed in a cluster, and offers new insights into the survivability of cool cores in the context of hierarchical structure formation.