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HST observations of NGC 6240

J. Gerssen·R. P. van der Marel·D. Axon·C. Mihos·L. Hernquist·J. E. Barnes
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Abstract

WFPC2 images and STIS spectroscopic observations are presented of the double nucleus in the merger system NGC 6240. We find that: (a) the kinematics of the ionized gas is similar to that of the molecular gas, despite a different morphology; (b) the gaseous and stellar kinematics are quite different, suggesting an early merger stage; (c) neither the gaseous nor the stellar kinematics show an obvious sign of the supermassive black hole believed to be responsible for the X-ray emission of NGC 6240; and (d) the steep off-nuclear velocity gradient is not due to a 10E11 solar mass black hole, in contrast to earlier suggestions.

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J. Gerssen, R. P. van der Marel, D. Axon, C. Mihos, L. Hernquist, J. E. Barnes. 2001-06-20. HST observations of NGC 6240. https://arxiv.org/abs/astro-ph/0106368

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