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Chandra Observations of Arp 220: The Nuclear Source

D. L. Clements·J. C. McDowell·S. Shaked·A. C. Baker·K. Borne·L. Colina·S. Lamb·C. Mundell
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Abstract

We present the first results from 60ks of observations of Arp 220 using the ACIS-S instrument on Chandra. We report the detection of several sources near the galaxy's nucleus, including a point source with a hard spectrum that is coincident with the western radio nucleus B. This point source is mildly absorbed (N_H ~ 3 x 10^22 cm^-2) and has an estimated luminosity of 4 x 10^40 erg/s. In addition, a fainter source may coincide with the eastern nucleus A. Extended hard X-ray emission in the vicinity raises the total estimated nuclear 2-10 keV X-ray luminosity to 1.2 x 10^41 erg/s, but we cannot rule out a hidden AGN behind columns exceeding 5 x 10^24 cm^-2. We also detect a peak of soft X-ray emission to the west of the nucleus, and a hard point source 2.5 kpc from the nucleus with a luminosity of 6 x 10^39 erg/s.

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D. L. Clements, J. C. McDowell, S. Shaked, A. C. Baker, K. Borne, L. Colina, S. Lamb, C. Mundell. 2002-08-27. Chandra Observations of Arp 220: The Nuclear Source. https://doi.org/10.1086/344439

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