J/A+A/587/A96 Mid-J CO shock tracing observations of IRDCs II (Pon+, 2016)
Mid-J CO shock tracing observations of infrared dark clouds.
II. Low-J CO constraints on excitation, depletion, and kinematics.
Pon A., Johnstone D., Caselli P., Fontani F., Palau A., Butler M.J.,
Kaufman M., Jimenez-Serra I., Tan J.C.
<Astron. Astrophys. 587, A96 (2016)>
=2016A&A...587A..96P 2016A&A...587A..96P (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Radio sources ; Carbon monoxide ; Spectroscopy
Keywords: ISM: clouds - stars: formation - ISM: molecules -
ISM: kinematics and dynamics - ISM: structure - ISM: abundances
Abstract:
Infrared dark clouds are kinematically complex molecular structures in
the interstellar medium that can host sites of massive star formation.
We present maps measuring 4 square arcminutes of the 12CO, 13CO,
and C18O J=3 to 2 lines from selected locations within the C and F
(G028.37+00.07 and G034.43+00.24) infrared dark clouds (IRDCs), as
well as single pointing observations of the 13CO and C18O J=2 to 1
lines towards three cores within these clouds. We derive CO gas
temperatures throughout the maps and find that CO is significantly
frozen out within these IRDCs. We find that the CO depletion tends to
be the highest near column density peaks with maximum depletion
factors between 5 and 9 in IRDC F and between 16 and 31 in IRDC C. We
also detect multiple velocity components and complex kinematic
structure in both IRDCs. Therefore, the kinematics of IRDCs seem to
point to dynamically evolving structures yielding dense cores with
considerable depletion factors.
Description:
Fits files of individual spectra taken with the IRAM 30m telescope.
The files are named such that the first two characters give the source
name while the next four characters give the isotopologue. All data
are for the J=2-1 transition. The data has already been reduced and
intensities are given in units of Tmb.
Objects:
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RA (ICRS) DE Designation(s)
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18 42 46.7 -04 04 08 C1 = [BT2009] C1
18 53 16.4 +01 26 20 F1 = [BT2009] F1
18 53 18.3 +01 27 13 F2 = [BT2009] F2
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 127 6 List of fits spectra
fits/* . 6 Individual fits spectra
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 24 I5 --- Nx Number of points
26- 48 A23 "date" Obs.date Observation date (YYYY-MM-DDThh:mm:ss.sss)
50- 61 E12.6 Hz bFREQ Lower value of frequency interval
63- 73 E11.6 Hz BFREQ Upper value of frequency interval
75- 80 I6 Hz dFREQ [195312] Frequency resolution
82- 83 I2 Kibyte size [90] Size of FITS file
85- 95 A11 --- FileName Name of FITS file, in subdirectory fits
97-127 A31 --- Title Title of the FITS file
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Acknowledgements:
Andy Pon, andyrpon(at)gmail.com
References:
Pon et al. Paper I 2015A&A...577A..75P 2015A&A...577A..75P
(End) Andy Pon [UWO, Canada], Patricia Vannier [CDS] 28-Dec-2015