J/A+A/606/A133 IRDC G035.39-00.33 NH3 and CCS data cubes (Sokolov+, 2017)
Temperature structure and kinematics of the IRDC G035.39-00.33.
Sokolov V., Wang K., Pineda J.E., Caselli P., Henshaw J.D., Tan J.C.,
Fontani F., Jimenez-Serra I., Lim W.
<Astron. Astrophys. 606, A133 (2017)>
=2017A&A...606A.133S 2017A&A...606A.133S (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Infrared sources
Keywords: ISM: kinematics and dynamics - ISM: clouds - stars: formation -
ISM: individual objects: G035.39-00.33
Abstract:
Infrared dark clouds represent the earliest stages of high-mass star
formation. Detailed observations of their physical conditions on all
physical scales are required to improve our understanding of their
role in fueling star formation.
We investigate the large-scale structure of the IRDC G035.39-00.33,
probing the dense gas with the classical ammonia thermometer. This
allows us to put reliable constraints on the temperature of the
extended, pc-scale dense gas reservoir and to probe the magnitude of
its non-thermal motions. Available far-infrared observations can be
used in tandem with the observed ammonia emission to estimate the
total gas mass contained in G035.39-00.33.
We identify a main velocity component as a prominent filament,
manifested as an ammonia emission intensity ridge spanning more than 6
pc, consistent with the previous studies on the Northern part of the
cloud. A number of additional line-of-sight components are found, and
a large-scale linear velocity gradient of ∼0.2km/s/pc is found along
the ridge of the IRDC. In contrast to the dust temperature map, an
ammonia-derived kinetic temperature map, presented for the entirety of
the cloud, reveals local temperature enhancements towards the massive
protostellar cores. We show that without properly accounting for the
line of sight contamination, the dust temperature is 2-3K larger than
the gas temperature measured with NH3.
While both the large-scale kinematics and temperature structure are
consistent with that of starless dark filaments, the kinetic gas
temperature profile on smaller scales is suggestive of tracing the
heating mechanism coincident with the locations of massive
protostellar cores.
Description:
The files included are the calibrated spectral cubes, in main beam
temperature units. They cover the K-band GBT observations of the
infrared dark cloud G035.39-00.33, mapped in two ammonia inversion
lines, (1, 1) and (2, 2), and CCS (2-1) rotational transition.
Objects:
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RA (2000) DE Designation(s)
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18 57 09.0 +02 07 46 IRDC G035.39-00.33 = MSXDC G035.39-0.33
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 112 3 List of datacubes
fits/* . 3 Individual data cubes
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See also:
J/ApJ/651/L125 : Water masers associated with IR dark cloud cores (Wang+, 2006)
J/ApJ/639/227 : MSX IRDC candidate catalog (Simon+, 2006)
J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)
J/ApJ/686/384 : 12CO, 13CO, C18O survey of IRDCs (Du+, 2008)
J/ApJ/715/310 : Early stages of star formation in IRDCs (Rathborne+, 2010)
J/ApJ/756/60 : A 3mm line survey in 37 IR dark clouds (Sanhueza+, 2012)
J/A+A/598/A76 : Six infrared dark clouds multi-wavelength obs. (Zhang+, 2017)
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- 21 I2 --- Nx Number of pixels along X-axis
23- 24 I2 --- Ny Number of pixels along Y-axis
26- 29 I4 --- Nz Number of slices
31- 37 F7.4 km/s bVrad Lower value of velocity interval
39- 45 F7.4 km/s BVrad Upper value of velocity interval
47- 55 F9.7 km/s dVrad Velocity resolution
57- 61 I5 Kibyte size Size of FITS file
63- 72 A10 --- FileName Name of FITS file, in subdirectory fits
74-112 A39 --- Title Title of the FITS file
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Acknowledgements:
Vlas Sokolov, vsokolov(at)mpe.mpg.de
(End) Patricia Vannier [CDS] 20-Sep-2017