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ID: 731845.0, MPI für Astronomie / Publikationen_mpia
Mid-J CO shock tracing observations of iInfrared dark clouds. III. SLED fitting
Authors:
Date of Publication (YYYY-MM-DD):2016
Title of Journal:The Astrophysical Journal
Volume:827
Issue / Number:2
Start Page:id. 107 (22 pp)
Audience:Not Specified
Abstract / Description:Giant molecular clouds contain supersonic turbulence that can locally heat small fractions of gas to over 100 K. We run shock models for low-velocity, C-type shocks propagating into gas with densities between 103 and 105 cm‑3 and find that CO lines are the most important cooling lines. Comparison to photodissociation region (PDR) models indicates that mid-J CO lines (J = 8 \to 7 and higher) should be dominated by emission from shocked gas. In Papers I and II we presented CO J = 3 \to 2, 8 \to 7, and 9 \to 8 observations toward four primarily quiescent clumps within infrared dark clouds. Here we fit PDR models to the combined spectral line energy distributions and show that the PDR models that best fit the low-J CO emission underpredict the mid-J CO emission by orders of magnitude, strongly hinting at a hot gas component within these clumps. The low-J
Free Keywords:ISM: clouds; ISM: molecules; shock waves; stars: formation; turbulence
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI fÃ¼r Astronomie
Identifiers:ISSN:0004-637X %R 10.3847/0004-637X/827/2/107