Infra-red sources in the H II region W3.
Abstract
High resolution mapping and photometric observations in the wavelength range I 65-20 have led to the discovery of nine distinct infra-red objects in W3. Four of them, including one coincident with W3(OH), are identified with compact radio H ii condensations 0.1 pc in diameter. They show strong emission in the range 3-20 jL which is attributable to dust grains at a temperature of 150 K mixed with the ionized gas. On the other hand, the 2- emission from these objects is considerably less than is predicted from the radio measurements, indicating that the H ii condensations are surrounded by obscuring dust with up to 50 mag of visual extinction. One of the condensations contains an unresolved source which is almost certainly a highly obscured O star that excites the component. Four other infra-red sources have no associated radio continuum source; one of these, an unresolved source with a luminosity 3 x io L0, is coincident with a source of H2O maser emission and may be a massive protostar.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- 1972
- DOI:
- 10.1093/mnras/160.1.1
- Bibcode:
- 1972MNRAS.160....1W