Astronomy and Astrophysics – Astrophysics
Scientific paper
Dec 1990
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1990a%26a...240..400g&link_type=abstract
Astronomy and Astrophysics (ISSN 0004-6361), vol. 240, no. 2, Dec. 1990, p. 400-408.
Astronomy and Astrophysics
Astrophysics
23
Abundance, Hydroxyl Radicals, Molecular Clouds, Carbon Monoxide, Cosmic Dust, Emission Spectra, Formaldehyde, Gravitational Effects
Scientific paper
Observations are presented of the (C-12)O, (C-13)O, OH, and H2CO ground state transitions in a small molecular cloud in the Polaris Flare - a huge cloud complex covering 40 square degrees probably at a distance of about 200 pc. The appearance of the cloud in visual, far infrared and (C-12)O emission is consistent with a collision between the cloud and an expanding shell. OH and (C-13)O column densities are well correlated with the IRAS 100-micron dust emission. If (C-13)O is converted to H2 column density assuming a conversion factor of 500,000, these relations indicate that the OH abundance is higher than in dark clouds and even somewhat higher than in diffuse clouds. Also the H2CO abundance is similar or larger than in dark clouds. As a further result the observations of the 1667 MHz and 1665 MHz OH transitions show main line anomalies in this high-latitude cloud i.e., non-LTE conditions for the levels involved.
Grossmann Volkmar
Heithausen Andreas
Mebold Ulrich
Meyerdierks H.
No associations
LandOfFree
A high-latitude cloud with increased hydroxyl abundance 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 A high-latitude cloud with increased hydroxyl abundance, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A high-latitude cloud with increased hydroxyl abundance will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1628117