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arXiv · astro-ph/9909351

Near-infrared photometry of isolated spirals with and without an AGN. I: The Data

Abstract

We present infrared imaging data in the J and K' bands obtained for 18 active spiral galaxies, together with 11 non active galaxies taken as a control sample. All of them were chosen to satisfy well defined isolation criteria so that the observed properties are not related to gravitational interaction. For each object we give: the image in the K' band, the sharp-divided image (obtained by dividing the observed image by a filtered one), the difference image (obtained by subtracting a model to the observed one), the color J-K' image, the ellipticity and position angle profiles, the surface brightness profiles in J and K', their fits by bulge+disk models and the color gradient. We have found that four (one) active (control) galaxies previously classified as non-barred turn out to have bars when observed in the near-infrared. One of these four galaxies (UGC 1395) also harbours a secondary bar. For 15 (9 active, 6 control) out of 24 (14 active, 10 control) of the optically classified barred galaxies (SB or SX) we find that a secondary bar (or a disk, a lense or an elongated ring) is present. The work presented here is part of a large program (DEGAS) aimed at finding whether there are differences between active and non active galaxies in the properties of their central regions that could be connected with the onset of nuclear activity.

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BibTeXRIS

I. Marquez, F. Durret, R. M. Gonzalez Delgado, I. Marrero, J. Masegosa, J. Maza, M. Moles, E. Perez, M. Roth. 1999-09-21. Near-infrared photometry of isolated spirals with and without an AGN. I: The Data. https://doi.org/10.1051/aas%3A1999516

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