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Soft X-Ray Sources at the Centers of the Elliptical Galaxies NGC 4472 and NGC 4649

D. Soldatenkov·A. Vikhlinin·M. Pavlinsky
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Abstract

Analysis of recent Chandra observations of the elliptical galaxies NGC 4472 and NGC 4649 has revealed faint soft X-ray sources at their centers. The sources are located to within 1'' of the optical centers of the galaxies. They are most likely associated with the central supermassive black holes. Interest in these and several other similar objects stems from the unusually low luminosity of the supermassive black holes embedded in dense interstellar medium. Our Chandra sources have very soft spectra. They are detectable only below ~0.6 keV and have luminosities in the 0.2-2.5 keV energy band of ~ 6 * 10^{37} erg/s and ~1.7 * 10^{38} erg/s in NGC 4649 and NGC 4472, respectively.

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D. Soldatenkov, A. Vikhlinin, M. Pavlinsky. 2003-06-30. Soft X-Ray Sources at the Centers of the Elliptical Galaxies NGC 4472 and NGC 4649. https://doi.org/10.1134/1.1573278

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