Model of Taurus molecular cloud 1 based on HC/sub 3/N observations
We have observed five rotational transitions of cyanoacetylene in the ark cloud TMC 1 and, using a Monte Carlo radiative transfer code, have produced a model of this source which is consistent with these observations. The interaction between radiative trapping and population equilibrium was solved for the 15 lowest rotational levels of HC/sub 3/N, assuming a cylindrical geometry for the source. The model, which we envisage as representing a compact condensation embedded well within Heiles' Cloud 2, is characterized by a relatively high excitation core and a lower excitation halo. Although we cannot rule out the possibility that the higher excitation of the core can be attributed solely to enhanced density there, we were unable to fit the observations well without involving a temperature enhancement as well. Transitions higher in frequency than the J = 8..-->..7 line originate predominantly in the core which is characterized by a kinetic temperature of 17 K and H/sub 2/ density of 6 x 10/sup 4/ cm/sup -3/. Corresponding values for the halo are 7 K and 8 x 10/sup 3/. The column density of HC/sub 3/N in TMC 1 is estimated to be 1.1 x 10/sup 14/ cm/sup -2/.
- Research Organization:
- Herzberg Institute of Astrophysics, National Research Council of Canada
- OSTI ID:
- 5289709
- Journal Information:
- Astrophys. J.; (United States), Vol. 254:1
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
INTERSTELLAR SPACE
PROPIOLONITRILE
ENERGY-LEVEL TRANSITIONS
ROTATIONAL STATES
COMPUTERIZED SIMULATION
ENERGY SPECTRA
ENERGY-LEVEL DENSITY
MOLECULES
MONTE CARLO METHOD
NEBULAE
RADIATION TRANSPORT
RADIOWAVE RADIATION
ELECTROMAGNETIC RADIATION
ENERGY LEVELS
EXCITED STATES
NITRILES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
RADIATIONS
SIMULATION
SPACE
SPECTRA
640105* - Astrophysics & Cosmology- Galaxies