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arXiv · astro-ph/0310669

Accretion and Outflow in the AGN and Starburst of NGC 5135

N. A. Levenson·K. A. Weaver·T. M. Heckman·H. Awaki·Y. Terashima
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Abstract

Observations of the Seyfert 2 and starburst galaxy NGC 5135 with the Chandra X-ray Observatory demonstrate that both of these phenomena contribute significantly to its X-ray emission. We spatially isolate the active galactic nucleus (AGN) and demonstrate that it is entirely obscured by column density N_H > 10^{24} cm^{-2}, detectable in the Chandra bandpass only as a strongly reprocessed, weak continuum and a prominent iron K alpha emission line with equivalent width of 2.4 keV. Most of the soft X-ray emission, both near the AGN and extending over several-kpc spatial scales, is collisionally-excited plasma. We attribute this thermal emission to stellar processes. The AGN dominates the X-ray emission only at energies above 4 keV. In the spectral energy distribution that extends to far-infrared wavelengths, nearly all of the emergent luminosity below 10 keV is attributable to star formation, not the AGN.

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N. A. Levenson, K. A. Weaver, T. M. Heckman, H. Awaki, Y. Terashima. 2003-10-22. Accretion and Outflow in the AGN and Starburst of NGC 5135. https://doi.org/10.1086/380836

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