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arXiv · 1401.6176

Young AGN outburst running over older X-ray cavities

Akos Bogdan·Reinout J. van Weeren·Ralph P. Kraft·William R. Forman·Scott Randall·Simona Giacintucci·Eugene Churazov·Christopher P. O'Dea·Stefi A. Baum·Jacob Noell-Storr·Christine Jones
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Abstract

Although the energetic feedback from active galactic nuclei (AGN) is believed to have a profound effect on the evolution of galaxies and clusters of galaxies, details of the AGN heating remain elusive. Here, we study NGC 193 - a nearby lenticular galaxy - based on X-ray (Chandra) and radio (VLA and GMRT) observations. These data reveal the complex AGN outburst history of the galaxy: we detect a pair of inner X-ray cavities, an outer X-ray cavity, a shock front, and radio lobes extending beyond the inner cavities. We suggest that the inner cavities were produced ~78 Myr ago by a weaker AGN outburst, while the outer cavity, the radio lobes, and the shock front are due to a younger (13-26 Myr) and (4-8) times more powerful outburst. Combining this with the observed morphology of NGC 193, we conclude that NGC 193 likely represents the first example of a second, more powerful, AGN outburst overrunning an older, weaker outburst. These results help to understand how the outburst energy is dissipated uniformly in the core of galaxies, and therefore may play a crucial role in resolving how AGN outbursts suppress the formation of large cooling flows at cluster centers.

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Akos Bogdan, Reinout J. van Weeren, Ralph P. Kraft, William R. Forman, Scott Randall, Simona Giacintucci, Eugene Churazov, Christopher P. O'Dea, Stefi A. Baum, Jacob Noell-Storr, Christine Jones. 2014-01-23. Young AGN outburst running over older X-ray cavities. https://doi.org/10.1088/2041-8205%2F782%2F2%2Fl19

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