A flattened cloud core in NGC 2024

DOI: 
Publication date: 
01/01/1993
Main author: 
Ho P.T.P.
IAA authors: 
Torrelles, J.M.;Gómez, J.F.
Authors: 
Ho P.T.P., Peng Y.-L., Torrelles J.M., Gómez J.F., Rodríguez L.F., Canto J.
Journal: 
Astrophysical Journal
Publication type: 
Article
Volume: 
408
Pages: 
565-572
Number: 
Abstract: 
The (J, K) = (1, 1) and (2, 2) NH3 lines were mapped toward a molecular cloud core in NGC 2024 using the VIA in its C/D-configuration. TWs region is associated with one of the most highly collimated molecular outflows. We find that the molecular condensations associated with the far-infrared souross FIR 5, FIR 6, and FIR 7 have kinetic temperatures TK ≃ 40 K. We also find line broadening toward FIR 6 and FIR 7. This suggests that these condensations may not be protostars heated by gravitational energy released during collapse but that they have an internal heating source. A flattened structure of ammonia emission is found extending parallel to the unipolar CO outflow structure, but displaced systematically to he east. If the NH3 emission traces the denser gas environment, there is no evidence that a dense gas structure is confining the molecular outflow. Instead, the location of the high-velocity outflow along the surface of the NH3 structure suggests that a wind is sweeping material from the surface of this elongated cloud core.
Database: 
SCOPUS
Keywords: 
ISM: individual (NGC 2024); ISM: jets and outflows; ISM: molecules; Radio lines: ISM