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arXiv · 0709.1336

X-ray active galactic nuclei in the core of the Perseus cluster

Abstract

We present a study of the X-ray emission from the nuclei of galaxies observed in the core of the Perseus cluster in a deep exposure with Chandra. Point sources are found coincident with the nuclei of 13 early-type galaxies, as well as the central galaxy NGC1275. This corresponds to all galaxies brighter than M_B = -18 in the Chandra field. All of these sources have a steep power-law spectral component and four have an additional thermal component. The unabsorbed power-law luminosities in the 0.5-7.0 keV band range from 8.10^38-5.10^40 erg/s. We find no simple correlations between the K band luminosity, or the FUV and NUV AB magnitudes of these galaxies and their X-ray properties. We have estimated the black hole masses of the nuclei using the K band M_BH-L_K relation and again find no correlation between black hole mass and the X-ray luminosity. Bondi accretion onto the black holes in the galaxies with mini-haloes should make them much more luminous than observed.

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S. Santra, J. S. Sanders, A. C. Fabian. 2007-09-10. X-ray active galactic nuclei in the core of the Perseus cluster. https://doi.org/10.1111/j.1365-2966.2007.12437.x

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