Bibcode
Pérez-Ramírez, D.; Knapen, J. H.; Peletier, R. F.; Laine, S.; Doyon, R.; Nadeau, D.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 317, Issue 2, pp. 234-248.
Advertised on:
9
2000
Citations
51
Refereed citations
47
Description
We present subarcsecond-resolution, ground-based, near-infrared images
of the central regions of a sample of 12 barred galaxies with
circumnuclear star formation activity, which is organized in ring-like
regions typically 1kpc in diameter. We also present Hubble Space
Telescope near-infrared images of 10 of our sample galaxies, and compare
them with our ground-based data. Although our sample galaxies were
selected for the presence of circumnuclear star formation activity, our
broad-band near-infrared images are heterogeneous, showing a substantial
amount of small-scale structure in some galaxies, and practically none
in others. We argue that, where it exists, this structure is caused by
young stars, which also cause the characteristic bumps or changes in
slope in the radial profiles of ellipticity, major axis position angle,
surface brightness and colour at the radius of the circumnuclear ring in
most of our sample galaxies. In seven out of 10 HST images, star
formation in the nuclear ring is clearly visible as a large number of
small emitting regions, organized into spiral arm fragments, which are
accompanied by dust lanes. Near-infrared colour index maps show much
more clearly the location of dust lanes and, in certain cases, regions
of star formation than single broad-band images. Circumnuclear spiral
structure thus outlined appears to be common in barred spiral galaxies
with circumnuclear star formation.