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The core structure of AGN: perils of adaptive optics artifacts

Scott C. Chapman·Simon L. Morris·Gordon A. H. Walker
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Abstract

As part of a project to map nearby Seyfert galaxies in the near-IR with adaptive optics, we present high spatial resolution, near-IR images in J,H, and K of the nuclei of NGC 3227 and NGC 2992, obtained with the Adaptive Optics Bonnette (AOB) on CFHT. The ~0.15" resolution allows us to probe structures in the core region at unprecedented scales. With NGC 3227, we are able to identify an inwards spiraling starburst in all three near-IR bands. NGC 2992 shows evidence for emission along a radio loop. Compared with HST optical images, dust obscuration becomes significantly less pronounced at longer wavelengths, revealing the true geometry of the core regions. The observed structures may help to elucidate fueling mechanisms for the central engine, as well as providing insight into the unification paradigms. The results are tempered with the discovery of AOB-related artifacts in the central arcsec of observed AGN galaxies which take on the appearance of spiral/disk structures.

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Scott C. Chapman, Simon L. Morris, Gordon A. H. Walker. 1998-10-22. The core structure of AGN: perils of adaptive optics artifacts. https://arxiv.org/abs/astro-ph/9810250

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