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Nuclear Components in the Bulges of Disk Galaxies

M. Balcells·L. Dominguez-Palmero·A. Graham·R. F. Peletier
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Abstract

By combining surface brightness profiles from images taken in the HST/NICMOS F160W and ground-based (GB) $K$ bands, we have obtained NIR profiles for a well studied sample of inclined disk galaxies, spanning radial ranges from 20 pc to a few kpc. We fit PSF-convolved Sersic-plus-exponential laws to the profiles, and compare the results with the fits to the ground-based data alone. HST profiles show light excesses over the best-fit Sersic law in the inner ~1 arcsec. This is often as a result of inner power-law cusps similar to the inner profiles of intermediate-luminosity elliptical galaxies.

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M. Balcells, L. Dominguez-Palmero, A. Graham, R. F. Peletier. 2001-06-22. Nuclear Components in the Bulges of Disk Galaxies. https://arxiv.org/abs/astro-ph/0106413

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