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arXiv · astro-ph/9905066

Morphology of the 12-micron Seyfert Galaxies: II. Optical and Near-Infrared Image Atlas

Abstract

We present 263 optical and near-infrared (NIR) images for 42 Seyfert 1s and 48 Seyfert 2s, selected from the Extended 12-micron Galaxy Sample. Elliptically-averaged profiles are derived from the images, and isophotal radii and magnitudes are calculated from these. We also report virtual aperture photometry, that judging from comparison with previous work, is accurate to roughly 0.05mag in the optical, and 0.07mag in the NIR. Our B-band isophotal magnitude and radii, obtained from ellipse fitting, are in good agreement with those of RC3. When compared with the B band, V, I, J, and K isophotal diameters show that the colors in the outer regions of Seyferts are consistent with the colors of normal spirals. Differences in the integrated isophotal colors and comparison with a simple model show that the active nucleus+bulge is stronger and redder in the NIR than in the optical. Finally, roughly estimated Seyfert disk surface brightnesses are significantly brighter in B and K than those in normal spirals of similar morphological type.

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L. K. Hunt, M. A. Malkan, B. Rush, M. D. Bicay, B. O. Nelson, R. M. Stanga, W. Webb. 1999-05-06. Morphology of the 12-micron Seyfert Galaxies: II. Optical and Near-Infrared Image Atlas. https://doi.org/10.1086/313279

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