Grand-Design Spirals in the Core of NGC 5248

Laine, S.; Knapen, J. H.; Pérez-Ramírez, D.; Doyon, R.; Nadeau, D.
Bibliographical reference

Astrophysics and Space Science, v. 276, Issue 2/4, p. 475-482 (2001).

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3
2001
Number of authors
5
IAC number of authors
0
Citations
0
Refereed citations
0
Description
We report the detection of a bisymmetric nuclear spiral structure in the spiral galaxy NGC 5248. The two red spiral arms can be followed for about 3 arcsec, before they appear to end inside the radius of the circumnuclear starburst `ring' at about 5.5 arcsec or 400 pc distance from the nucleus. We combine our near-infrared Canada-France-Hawaii Telescope adaptive optics images with traditional near-infrared and optical images and show that spiral structure is present in this galaxy at spatial scales reaching from a hundred parsecs to 15 kpc. Comparison with a Hubble Space Telescope ultraviolet image shows how the starburst ring is related to the nuclear spiral structure. We also show a two-dimensional H_α velocity field that reveals no evidence for systematic streaming motions near the nuclear spiral or the starburst ring, nor for a rapidly rising rotation curve.