Astronomy and Astrophysics – Astronomy
Scientific paper
May 1991
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1991apj...372..185l&link_type=abstract
Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 372, May 1, 1991, p. 185-193. Research sponsored by National Research Counc
Astronomy and Astrophysics
Astronomy
77
Cosmic Dust, Dark Matter, Infrared Sources (Astronomy), Molecular Clouds, Emission Spectra, Infrared Astronomy Satellite, Interstellar Matter, Nebulae
Scientific paper
IRAS maps at 60 and 100 microns of the complex of dark clouds containing L1345, L183, and L1780 are presented and discussed. Extended regions are apparent where the 60 micron emission is very low compared to the 100 micron emission. The 60-100 micron flux ratio has a constant value of 0.2 in the outer diffuse parts of the clouds but suddenly drops to less than 0.03 in the opaque cloud centers. A geometrical model is used to show that the drop occurs in a narrow transition layer that has not been resolved by IRAS. The observations provide direct evidence for dust temperatures colder than 15 K in dark clouds. A number of 60 micron-deficient regions are defined using the quantity Delta I(100) = I(60)/Theta, where Theta is the ratio I(60)/I(100) in the diffuse parts of the complex. Delta I(100) is highly proportional to extinction and (C-13)O column density. The relationships indicate that the dust temperature must be constant over a large fraction of the volume sampled by Delta I(100). An upper limit of 4.8 g/sq cm is obtained for the mass absorption coefficient of dust at 100 microns.
Clark Frank O.
Laureijs Rene J.
Prusti Timo
No associations
LandOfFree
IRAS detection of very cold dust in the LYNDS 134 cloud complex does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with IRAS detection of very cold dust in the LYNDS 134 cloud complex, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and IRAS detection of very cold dust in the LYNDS 134 cloud complex will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1036277