Extinction and reddening of HII regions in the Small Magellanic Cloud.
Abstract
We present absolute Hα and Hβ fluxes, obtained with a Fabry-Perot spectrophotometer, of 24 bright HII regions in the Small Magellanic Cloud. The photographic Hα maps of Kennicutt & Hodge (1986) are re-calibrated using these new Hα fluxes; the new calibration gives fluxes 25% smaller than those previously published. These photographic and photoelectric Hα data are used in conjunction with radio continuum observations at 843 MHz from the Molonglo Observatory Synthesis Telescope to study the dust associated with SMC HII regions. For most regions the derived reddenings and extinctions are compatible with the standard Galactic extinction law and uniform interstellar extinction. A few regions display relatively high reddening and extinction; these are bright compact sources, such as N13AB, N27 and the cores of N81 and N88, all of which probably have closely associated dust. Low resolution Hi observations do not detect these high concentrations of dust.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 1996
- Bibcode:
- 1996A&A...307..403C
- Keywords:
-
- MAGELLANIC CLOUDS;
- HII REGIONS;
- DUST;
- EXTINCTION;
- GALAXIES: ISM