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arXiv · astro-ph/9908222

Adaptive optics near-IR imaging of NGC2992 - unveiling core structures related to radio figure-8 loops

Abstract

We present near-IR adaptive optics, VLA radio and HST optical imaging of the nearby Seyfert galaxy NGC2992. Spiral structure and an extension to the West are traced down to the core region at the limiting resolution of our near-IR images. A faint, diffuse loop of near-IR and radio emission is also observed to the north, embedded within the prominent 2 arcsec radio loop previously observed to the northwest. Near-IR color maps, and CO narrowband imaging, are then used to identify which regions may not be purely reddened stellar populations. Our new data provide evidence that the VLA radio-loop morphology in the shape of a figure-8 represents two components superimposed: 1) outflow bubbles out of the plane of the disk, coincident with the extended emission line region (EELR); 2) star formation along the spiral arm within the galaxy disk and through the dust lane. The near-IR continuum emission associated with the outflowing radio bubbles suggest that the radio loops are driven by the active nucleus.

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Scott C. Chapman, Simon L. Morris, Almudena Alonso-Herrero, Heino Falcke. 1999-08-20. Adaptive optics near-IR imaging of NGC2992 - unveiling core structures related to radio figure-8 loops. https://doi.org/10.1046/j.1365-8711.2000.03303.x

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