The Complex X-Ray Morphology of NGC 7618: A Major Group-Group Merger in the Local Universe?

  title={The Complex X-Ray Morphology of NGC 7618: A Major Group-Group Merger in the Local Universe?},
  author={Ralph P. Kraft and C. Jones and P. E. J. Nulsen and Martin J. Hardcastle},
  journal={The Astrophysical Journal},
We present results from a short Chandra ACIS-S observation of NGC 7618, the dominant central galaxy of a nearby (z = 0.017309, d = 74.1 Mpc) group. We detect a sharp surface brightness discontinuity 14.4 kpc north of the nucleus subtending an angle of 130° with an X-ray tail extending ~70 kpc in the opposite direction. The temperature of the gas inside and outside the discontinuity is 0.79 ± 0.03 and 0.81 ± 0.07 keV, respectively. There is marginal evidence for a discontinuous change in the… 

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