Microwave spectral lines in galactic dust globules
Citations Over TimeTop 10% of 1978 papers
Abstract
Results are presented for a study of 12 galactic dust globules based on observations of various microwave transitions of CO, (C-13)O, C(O-18), CS, C(S-34), NH3, H2CO, and OH. The emission or absorption of the different molecular transitions are compared, and a consistent set of physical and chemical parameters is derived for each globule. Spectra taken at the center positions of the globules IC 1848-1, ORI-I-2, B227, L134, B68, B335m and B163 are provided, and the observational results for these seven globules are evaluated separately for each molecule. Simple thermal models are used to interpret the results, the physical characteristics of globules in general and of each globule in particular are discussed, and eight globules are found to have a mass greater than the appropriate Jeans mass. It is shown that: (1) the extent of molecular emission (or H2CO absorption) correlates very well with the optical images of the dust globules; (2) CO is probably present wherever there is dust; (3) the kinetic temperature in all but one of the 12 globules is about 10 K; and (4) all the globules studied appear to be gravitationally bound objects and are probably undergoing gravitational collapse.
Related Papers
- → The Cosmic Microwave Background Spectrum(1997)4 cited
- → CMB Quadrupole induced polarisation from clusters and filaments(2004)
- Cosmological Parameter Estimation from CMB and X-ray clusters(2001)
- → Future projects on the Cosmic Microwave Background(2008)