A Model of Compact H II Regions Emitting in the Infrared
Abstract
Summary. The compact H ii regions, which are strong emitting sources in the infrared, are studied. The following conclusions are drawn. (1)The size of the region is determined by the luminosity of the source of radiative energy, and the density of the region. (2)The dust grains in these compact regions have the same properties as the dust grains in the general interstellar medium. (3)The correlation between observed infrared flux and observed radio flux can be explained for those cases in which a single star is the energy source; this correlation s a result of the correlation between the temperature and the luminosity of the star. In those H ii regions in which many stars are responsible for the heating, it is predicted that no correlation will be observed. (4) The absorption efficiency of the dust grains as a function of wavelength between 20 and 350 cannot have the form - over the entire range, regardless of the value of n, if the optical depth is small in this wavelength region. Key words: dust grains - absorption and emission by dust - interstellar matter - compact H ii regions
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 1974
- Bibcode:
- 1974A&A....30..371P