The thermal and non-thermal components of sixteen nebular complexes

The nature of the fine structure of sixteen galactic nebular complexes is investigated by producing their radio spectra. The complexes are: W31, W33, W35, K39, W42, W40, W43, W48, W47, W49, K47, W51, W3, Carina, NGC 6334 and NGC 6357. Various physical parameters of the thermal components are derived by adopting a homogeneous, optically thin, spherical model. The variations of the physical parameters derived from the model as a function of the electron temperature and distance are investigated. A discussion about the thermal and non-thermal spectra is included. Some simple statistics on the physical parameters of the thermal sources (diameter, density, mass) are also presented by employing a sample of sixty-seven thermal components.