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arXiv · 1101.3659

The location of an active nucleus and the soft X-ray shadowing by a tidal tail in the ULIRG Mrk 273

K. Iwasawa·J. M. Mazzarella·J. A. Surace·D. B. Sanders·L. Armus·A. S. Evans·J. H. Howell·S. Komossa·A. O. Petric·S. H. Teng·Vivian U·S. Veilleux
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Abstract

Analysis of data from the Chandra X-ray Observatory for the double nucleus ULIRG Mrk 273 reveals an absorbed hard X-ray source coincident with the southwest nucleus, implying that this unresolved near infrared source is where an active nucleus resides while the northern nuclear region contains a powerful starburst which dominates the far infrared luminosity. There is evidence of a slight image extension in the 6-7 keV band, where a Fe K line is present, towards the northern nucleus. A large-scale, diffuse emission nebula detected in soft X-rays contains a dark lane that spatially coincides with a high surface-brightness tidal tail extending ~50 arcsec (40 kpc) to the south. The soft X-ray source is likely located behind the tidal tail which absorbs X-ray photons along the line of sight. The estimated column density of cold gas in the tidal tail responsible for shadowing the soft X-rays is nH >= 6e+21 cm-2, consistent with the tidal tail having an edge-on orientation.

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K. Iwasawa, J. M. Mazzarella, J. A. Surace, D. B. Sanders, L. Armus, A. S. Evans, J. H. Howell, S. Komossa, A. O. Petric, S. H. Teng, Vivian U, S. Veilleux. 2011-01-19. The location of an active nucleus and the soft X-ray shadowing by a tidal tail in the ULIRG Mrk 273. https://doi.org/10.1051/0004-6361/201015872

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