Statistics and properties of H II regions in a sample of grand-design galaxies. II. Physical properties.

Bibcode
1996A&A...312..275R
Rozas, M.; Knapen, J. H.; Beckman, J. E.
Bibliographical reference

Astronomy and Astrophysics, v.312, p.275-282

Advertised on:
8
1996
Journal
Astronomy and Astrophysics
Number of authors
3
IAC number of authors
1
Citations
35
Refereed citations
30
Description
We describe statistical properties of complete samples of HII regions in the grand-design spiral galaxies NGC 157, NGC 3631, NGC 6764 and NGC 6951. We use the catalogues of HII regions obtained from high-quality Hα line images by Rozas et al. . Slopes and zero points of diameter distribution functions for these four galaxies coincide well with values published for other galaxies of similar morphological type. We also present density distributions and Hα scale lengths, as well as luminosity-volume and number-luminosity-size relations. The latter relations show evidence for the presence of a population of high luminosity density-bounded HII regions in the spiral arms. We see the change from ionization- to density-bounded HII regions occur clearly at a specific HII region flux level.
Type
Refereed
Galaxies

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