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arXiv · 1108.0955

Looking inside the nest: the hidden structure of the merger galaxy NGC 1316 (Fornax A)

Y. Beletsky·D. A. Gadotti·A. Moiseev·J. Alves·A. Kniazev
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Abstract

We present an analysis of the circumnuclear structure of NGC 1316 using both near-infrared imaging and stellar kinematics. 2D decomposition of the images suggests the presence of a structure that resembles inner gaseous spiral arms, at about 5 to 15" from the center (500 to 1500 pc). We also find a disc-like stellar structure with radius less than 200 pc. Analysis of previously published SINFONI integral field kinematics data indicates a kinematically decoupled core in the same spatial scale, further evidence that indeed the nuclear stellar structure found is a kinematically cold stellar disc. We suggest that both newly-found structural components are the result of a recent accretion of a companion galaxy.

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Y. Beletsky, D. A. Gadotti, A. Moiseev, J. Alves, A. Kniazev. 2011-08-03. Looking inside the nest: the hidden structure of the merger galaxy NGC 1316 (Fornax A). https://doi.org/10.1111/j.1745-3933.2011.01130.x

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