Spatially Resolved Circumnuclear Dust in Centaurus A

Margarita Karovska; Massimo Marengo; Martin Elvis; Giovanni Fazio; Joseph Hora; Philip Hinz; William Hoffmann; Michael Meyer; Eric Mamajek

doi:10.1086/380816

arXiv · astro-ph/0311139

Spatially Resolved Circumnuclear Dust in Centaurus A

Margarita Karovska·Massimo Marengo·Martin Elvis·Giovanni Fazio·Joseph Hora·Philip Hinz·William Hoffmann·Michael Meyer·Eric Mamajek

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Abstract

In this paper we present results from our exploratory mid-IR study of Centaurus A circumnuclear environment using high-angular resolution imaging at the Magellan 6.5m telescope with the MIRAC/BLINC camera. We detected emission from a compact region surrounding the nuclear source, and obtained photometry at 8.8 microns and in the N band. Our analysis suggests that the nuclear region is resolved with a size of approximately 3 pc. The mid-IR emission from this region is likely associated with cool dust with an estimated temperature of \~160 K, surrounding the central ``hidden'' AGN. We discuss the characteristics of this emission in relation to other mid-IR observations and the implications on models of dust formation in AGNs.

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Margarita Karovska, Massimo Marengo, Martin Elvis, Giovanni Fazio, Joseph Hora, Philip Hinz, William Hoffmann, Michael Meyer, Eric Mamajek. 2003-11-05. Spatially Resolved Circumnuclear Dust in Centaurus A. https://doi.org/10.1086/380816

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