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arXiv · astro-ph/9611013

Ejection of Matter and Energy from NGC 4258

E. M. Burbidge·G. Burbidge
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Abstract

It has been claimed that the megamaser observations of the nucleus of NGC 4258 show that a massive black hole is present in its center (Miyoshi et al. 1995, Greenhill et al. 1995). We show that the evidence of ejection of gas, radio plasma, and X-ray emitting QSOs from this nucleus all show that the ejection is coming from the center in a curving flow within a cone with angle ~40 degrees, centered at P.A. 100 degrees. This is close to the direction in which the velocities from the megamaser have been measured, so that the evidence taken as a whole suggests that the masering gas also is being ejected in the same direction at velocities +/- 900 km/sec and not rotating about a massive black hole. Thus it does not provide evidence for a black hole in the center. Subject headings: galaxies: nuclei: individual (NGC 4258) -- black holes -- masers

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E. M. Burbidge, G. Burbidge. 1996-11-03. Ejection of Matter and Energy from NGC 4258. https://doi.org/10.1086/310517

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