J/ApJ/936/80 ASHES. VI. Core-Scale CO Depletion (Sabatini+, 2022)
The ALMA Survey of 70um Dark High-mass Clumps in Early Stages (ASHES).
VI. The Core-scale CO Depletion.
Sabatini G., Bovino S., Sanhueza P., Morii K., Li S., Redaelli E.,
Zhang Q., Lu X., Feng S., Tafoya D., Izumi N., Sakai T., Tatematsu K.,
Allingham D.
<Astrophys. J., 936, 80 (2022)>
=2022ApJ...936...80S 2022ApJ...936...80S
ADC_Keywords: Star Forming Region; Interstellar medium; Stars, giant
Keywords: Infrared dark clouds ; Star forming regions ; Star formation ;
Massive stars ; Interstellar medium ; Astrochemistry ;
Interstellar line emission
Abstract:
Studying the physical and chemical properties of cold and dense
molecular clouds is crucial for the understanding of how stars form.
Under the typical conditions of infrared dark clouds, CO is removed
from the gas phase and trapped onto the surface of dust grains by the
so-called depletion process. This suggests that the CO-depletion
factor (fD) can be a useful chemical indicator for identifying cold
and dense regions (i.e., prestellar cores). We have used the 1.3mm
continuum and C18O (2-1) data observed at the resolution of ∼5000 au
in the ALMA Survey of 70µm Dark High-mass Clumps in Early Stages
(ASHES) to construct averaged maps of fD in 12 clumps to characterize
the earliest stages of the high-mass star formation process. The
average fD determined for 277 of the 294 ASHES cores follows an
unexpected increase from the prestellar to the protostellar stage. If
we exclude the temperature effect due to the slight variations in the
NH3 kinetic temperature among different cores, we explain this result
as a dependence primarily on the average gas density, which increases
in cores where protostellar conditions prevail. This shows that fD
determined in high-mass star-forming regions at the core scale is
insufficient to distinguish among prestellar and protostellar
conditions for the individual cores and should be complemented by
information provided by additional tracers. However, we confirm that
the clump-averaged fD values correlate with the luminosity-to-mass
ratio of each source, which is known to trace the evolution of the
star formation process.
Description:
In a pilot study (Paper I), 12 massive 70um dark clumps were mosaicked
with ALMA in the dust continuum at ∼224GHz (∼1.2" resolution) and used
to characterize clump fragmentation.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 27 301 Averaged fD computed for the whole core sample
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See also:
J/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)
J/ApJ/641/389 : Millimetric observations of IRDC cores (Rathborne+, 2006)
J/ApJ/639/227 : MSX IRDC candidate catalog (Simon+, 2006)
J/ApJ/653/1325 : Galactic distribution of infrared dark clouds (Simon+, 2006)
J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)
J/A+A/481/345 : SED evolution in massive YSOs (Molinari+, 2008)
J/A+A/501/539 : RMS survey. 6cm observations of YSOs (Urquhart+, 2009)
J/AJ/142/136 : Spectroscopy of Cepheids. l=30-250° (Luck+, 2011)
J/ApJ/756/60 : A 3mm line survey in 37 IR dark clouds (Sanhueza+, 2012)
J/A+A/570/A65 : ATLASGAL massive clumps CO depletion (Giannetti+, 2014)
J/ApJ/783/130 : Parallaxes of high mass star forming regions (Reid+, 2014)
J/ApJ/815/130 : High-mass molecular clumps from MALT90 (Guzman+, 2015)
J/A+A/592/A21 : Are infrared dark clouds really quiescent? (Feng+, 2016)
J/A+A/590/A72 : Herschel counterparts of SDC (Peretto+, 2016)
J/A+A/587/A96 : Mid-J CO shock tracing observations of IRDCs II (Pon+, 2016)
J/MNRAS/471/100 : Hi-GAL compact source catalog. -71.0<l<67.0 (Elia+, 2017)
J/A+A/603/A33 : Temperature evolution in massive clumps (Giannetti+, 2017)
J/A+A/599/A139 : ATLASGAL massive clump dust characterization (Koenig+, 2017)
J/A+A/602/A77 : HOBYS; 46 MDCs found in NGC 6334 (Tige+, 2017)
J/AJ/154/140 : MALT90 kinematic distancs molecular clumps (Whitaker+, 2017)
J/ApJS/237/27 : Radio Ammonia Mid-plane Survey pilot survey (Hogge+, 2018)
J/MNRAS/473/1059 : Complete sample of Galactic clump prop (Urquhart+, 2018)
J/ApJ/884/4 : KEYSTONE; ammonia structures in Galactic GMCs (Keown+, 2019)
J/A+A/642/A87 : Hub-filament candidates (Kumar+, 2020)
J/A+A/634/A115 : Orion B9 dense cores H2D+ spectra (Miettinen, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Clump IRDC Clump Name
17- 22 A6 --- Core ALMA Core Name (1)
24- 27 F4.1 --- fD [0.8/92.8]? Averaged CO-depletion factor
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Note (1): The classification of cores follows that defined in
Sanhueza+, 2019, J/ApJ/886/102.
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History:
From electronic version of the journal
References:
Sanhueza et al. Paper I. 2019ApJ...886..102S 2019ApJ...886..102S Cat. J/ApJ/886/102
Li et al. Paper II. 2020ApJ...903..119L 2020ApJ...903..119L
Tafoya et al. Paper III. 2021ApJ...913..131T 2021ApJ...913..131T
Morii et al. Paper IV. 2021ApJ...923..147M 2021ApJ...923..147M
Sakai et al. Paper V. 2022ApJ...925..144S 2022ApJ...925..144S
Sabatini et al. Paper VI. 2022ApJ...936...80S 2022ApJ...936...80S This catalog
Li et al. Paper VII. 2022ApJ...939..102L 2022ApJ...939..102L
Li et al. Paper VIII. 2023ApJ...949..109L 2023ApJ...949..109L Cat. J/ApJ/949/109
Morii et al. Paper IX. 2023ApJ...950..148M 2023ApJ...950..148M Cat. J/ApJ/950/148
Izumi at al. Paper X. 2024ApJ...963..163I 2024ApJ...963..163I
Morii et al. Paper XI. 2024ApJ...966..171M 2024ApJ...966..171M
(End) Prepared by [AAS], Coralie Fix [CDS], 20-Jun-2024