Structure of dense molecular gas in the TMC 1 from observations of three transitions of HC/sub 3/N

Journal Article · Fri Apr 01 04:00:00 EST 1983 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/160854· OSTI ID:5831348

Schloerb, F P; Snell, R L; Young, J S

We present high spatial resolution maps of the J = 5..-->..4, J = 9..-->..8, and J = 12..-->..11 transitions of HC/sub 3/N toward the interstellar cloud TMC 1 obtained with the Five College Radio Astronomy Observatory 14 m antenna. These transitions trace the high density molecular gas; the maps show that the dense material in TMC 1 is confined to a narrow ridge roughly 12' x 3' in extent. Maps of the source at individual velocities suggest that the ridge material is further divided into fragments which are in relative motion. The data are fitted to a cylindrical source model to determine the density and HC/sub 3/N column density within the ridge. The total mass of TMC 1 is approx.30 M/sub sun/, with each of the smaller fragments containing a few solar masses. The intensities of all three transitions are consistent with a single density of 5--10 x 10/sup 4/ cm/sup -3/; no variations in the density along the ridge are required by the data. The abundance of HC/sub 3/N in the models varies by approximately a factor of 3, from 10/sup -9/ at the cyanopolyne peak at the SE end of the ridge to 3 x 10/sup -10/ at the NH/sub 3/ peak to the NW. The present structure of TMC 1 probably resulted from the collapse and fragmentation of Heiles Cloud 2 and may eventually lead to the formation of stars.

• Research Organization: Five College Radio Astronomy Observatory, Department of Physics and Astronomy, University of Massachusetts, Amherst
• OSTI ID: 5831348
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 267:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
CHEMICAL COMPOSITION
CHEMISTRY
COSMIC GASES
COSMOCHEMISTRY
DISTRIBUTION
ENERGY-LEVEL TRANSITIONS
FLUIDS
GASES
MAPS
NEBULAE
NITRILES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROPIOLONITRILE
SPATIAL DISTRIBUTION