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A First Look at the Nuclear Region of M31 with Chandra

Michael R. Garcia·Stephen S. Murray·Francis A. Primini·William R. Forman·Jeffrey E. McClintock·Christine Jones
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Abstract

We report on the first observation of the nuclear region of M31 with the Chandra X-ray Observatory. The nuclear source seen with the Einstein and ROSAT HRIs is resolved into five point sources. One of these sources is within 1'' of the M31 central super-massive black hole. As compared to the other point sources in M31, this nuclear source has an unusual x-ray spectrum. Based on the spatial coincidence we identify this source with the central black hole, and note that the unusual spectrum is a challenge to current theories. A bright transient is detected ~26'' to the west of the nucleus, which may be associated with a stellar mass black hole.

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Michael R. Garcia, Stephen S. Murray, Francis A. Primini, William R. Forman, Jeffrey E. McClintock, Christine Jones. 2000-03-17. A First Look at the Nuclear Region of M31 with Chandra. https://doi.org/10.1086/312751

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