J/ApJS/231/11 High-mass starless clump candidates from ATLASGAL (Yuan+, 2017)
High-mass starless clumps in the inner galactic plane: the sample and
dust properties.
Yuan J., Wu Y., Ellingsen S.P., Evans II N.J., Henkel C., Wang K.,
Liu H.-L., Liu T., Li J.-Z., Zavagno A.
<Astrophys. J. Suppl. Ser., 231, 11-11 (2017)>
=2017ApJS..231...11Y 2017ApJS..231...11Y (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Millimetric/submm sources ; Surveys
Keywords: infrared: ISM; ISM: clouds; stars: formation; stars: massive;
submillimeter: ISM
Abstract:
We report a sample of 463 high-mass starless clump (HMSC) candidates
within -60°<l<60° and -1°<b<1°. This sample has been
singled out from 10861 ATLASGAL clumps. None of these sources are
associated with any known star-forming activities collected in SIMBAD
and young stellar objects identified using color-based criteria. We
also make sure that the HMSC candidates have neither point sources at
24 and 70µm nor strong extended emission at 24µm. Most of the
identified HMSCs are infrared dark, and some are even dark at 70µm.
Their distribution shows crowding in Galactic spiral arms and toward
the Galactic center and some well-known star-forming complexes. Many
HMSCs are associated with large-scale filaments. Some basic parameters
were attained from column density and dust temperature maps
constructed via fitting far-infrared and submillimeter continuum data
to modified blackbodies. The HMSC candidates have sizes, masses, and
densities similar to clumps associated with Class II methanol masers
and H II regions, suggesting that they will evolve into star-forming
clumps. More than 90% of the HMSC candidates have densities above some
proposed thresholds for forming high-mass stars. With dust
temperatures and luminosity-to-mass ratios significantly lower than
that for star-forming sources, the HMSC candidates are externally
heated and genuinely at very early stages of high-mass star formation.
Twenty sources with equivalent radii req<0.15pc and mass surface
densities Σ>0.08g/cm2 could be possible high-mass starless
cores. Further investigations toward these HMSCs would undoubtedly
shed light on comprehensively understanding the birth of high-mass
stars.
Description:
This work is based on data from several Galactic plane surveys
covering wavelengths from mid-IR to submillimeter.
The sample of dense clumps from the ATLASGAL survey (Schuller+
2009A&A...504..415S 2009A&A...504..415S) provides the basis for our investigation. The
ATLASGAL survey mapped 420 square degrees of the Galactic plane
between -80°<l<60°, using the LABOCA camera on the APEX
telescope at 870um with a 19.2" angular resolution. The astrometry of
the data set and the derived source positions have been assumed to be
the same as the pointing accuracy of the telescope, which is ∼2"-3".
Point-source catalogs from GLIMPSE (Spitzer/IRAC) and MIPSGAL
(Spitzer/MIPS) surveys have been used to identify possible young
stellar object (YSO) candidates associated with ATLASGAL clumps.
Far-IR data from the Hi-GAL survey (Herschel-PACS and -SPIRE) have
been used to further constrain the starless clump candidates and
investigate their dust properties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 85 463 Basic parameters of high-mass starless clump
(HMSC) candidates
table3.dat 75 463 Physical parameters of HMSC candidates
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
II/293 : GLIMPSE Source Catalog (I + II + 3D) (IPAC 2008)
VIII/96 : 6-GHz methanol multibeam maser catalogue (Caswell+, 2010-12)
J/A+A/291/943 : Protostellar cores (Ossenkopf+, 1994)
J/A+A/474/891 : 13CO obs. of YSOs in South Gal. plane (Urquhart+, 2007)
J/ApJ/680/349 : Galactic distribution of IRDCs (Jackson+, 2008)
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/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/A+A/499/149 : 1.2mm maps of southern Infrared Dark Clouds (Vasyunina+, 2009)
J/ApJ/723/1019 : Galactic SFR and gas surface densities (Heiderman+, 2010)
J/A+A/515/A55 : NGC 6334-NGC 6357 complex (Russeil+, 2010)
J/ApJ/720/1055 : VBLA observations of W51 Main/South (Sato+, 2010)
J/ApJ/741/110 : The BGPS. VII. Massive star-forming regions (Dunham+, 2011)
J/MNRAS/426/1972 : H2O Southern Gal. Plane Survey, HOPS. II (Purcell+, 2012)
J/A+A/540/A113 : Starless clumps in ATLASGAL (Tackenberg+, 2012)
J/A+A/544/A146 : ATLASGAL cold high-mass clumps with NH3 (Wienen+, 2012)
J/A+A/553/A115 : Millimetric and far-IR maps of IRDC 18310-4 (Beuther+, 2013)
J/A+A/549/A45 : ATLASGAL Compact Source Catalog: 330<l<21 (Contreras+, 2013)
J/ApJ/772/45 : Hi-GAL obs.: star formation in the 3rd quadrant (Elia+, 2013)
J/ApJS/208/11 : The Red MSX Source Survey: massive protostars (Lumsden+, 2013)
J/ApJS/209/2 : The BGPS. X. Dense molecular gas (Shirley+, 2013)
J/MNRAS/435/400 : ATLASGAL. Compact HII regions (Urquhart+, 2013)
J/A+A/549/A130 : YSOs in Herschel-Hi-GAL survey (Veneziani+, 2013)
J/A+A/565/A75 : ATLASGAL. Dust condensations in Gal. plane (Csengeri+, 2014)
J/A+A/568/A41 : ATLASGAL Compact Source Catalog: 280<l<60 (Urquhart+, 2014)
J/A+A/570/A65 : ATLASGAL massive clumps CO depletion (Giannetti+, 2014)
J/MNRAS/437/1791 : RMS survey: molecular observations (Urquhart+, 2014)
J/MNRAS/443/1555 : ATLASGAL massive star forming clumps (Urquhart+, 2014)
J/A+A/579/A91 : ATLASGAL inner Galaxy massive cold dust clumps (Wienen+, 2015)
J/A+A/581/A119 : Starless gas clump IRDC 18310-4 images (Beuther+, 2015)
J/AJ/149/64 : MIPSGAL 24µm point source catalog (Gutermuth+, 2015)
J/MNRAS/451/3089 : Young clumps embedded in IRDC (Traficante+, 2015)
J/A+A/586/A149 : SiO in ATLASGAL-selected massive clumps (Csengeri+, 2016)
J/A+A/591/A149 : Hi-GAL. inner Milky Way: +68≥l≥70 (Molinari+, 2016)
J/ApJ/822/59 : BGPS. XIV. Molecular cloud clumps GBT obs. (Svoboda+, 2016)
J/ApJ/824/29 : ATLASGAL clumps with IRAS flux & MALT90 data (Stephens+, 2016)
J/A+A/599/A139 : ATLASGAL massive clumps dust characterization (Koenig+, 2017)
J/A+A/602/A37 : Millimeter RRL in ATLASGAL massive clumps (Kim+, 2017)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- [CUS2014] Identifier (GLLL.llll+B.bbbb)
18- 19 I2 h RAh Hour of Right Ascension (J2000)
21- 22 I2 min RAm Minute of Right Ascension (J2000)
24- 28 F5.2 s RAs Second of Right Ascension (J2000)
30 A1 --- DE- Sign of the Declination (J2000)
31- 32 I2 deg DEd Degree of Declination (J2000)
34- 35 I2 arcmin DEm Arcminute of Declination (J2000)
37- 40 F4.1 arcsec DEs Arcsecond of Declination (J2000)
42- 43 I2 arcsec MajAxis [21/97] Angular major half-intensity axis
45- 46 I2 arcsec MinAxis [20/50] Angular minor half-intensity axis
48- 52 F5.1 deg PA Position angle (1)
54- 55 I2 arcsec FWHM [20/59] Full-Width at Half-Maximum
57- 63 F7.2 km/s VLSR [-122/206] Local Standard of Rest velocity
65- 69 F5.2 kpc Dist [0.2/19] Distance
71- 75 F5.2 kpc e_Dist Uncertainty in Dist
77- 81 A5 --- r_VLSR Reference for VLSR (2)
83 A1 --- Flag The 70 micron dark clump flag (3)
85 A1 --- f_[CUS2014] s : possible starless core;
column added by CDS following table 5
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Note (1): Corrected in the FK5 system with respect to the north direction.
Note (2): Reference as follows:
c14 = Csengeri et al. (2014, J/A+A/565/A75);
d11 = Dunham et al. (2011, J/ApJ/741/110);
d13 = Dempsey et al. (2013ApJS..209....8D 2013ApJS..209....8D);
j08 = Jackson et al. (2008, J/ApJ/680/349);
p12 = Purcell et al. (2012, J/MNRAS/426/1972);
s13 = Shirley et al. (2013, J/ApJS/209/2);
u07 = Urquhart et al. (2007, J/A+A/474/891);
u14 = Urquhart et al. (2014, J/MNRAS/437/1791);
w12 = Wienen et al. (2012, J/A+A/544/A146);
m90 = MALT90 (the Millimetre Astronomy Legacy Team 90GHz (MALT90) survey;
Jackson et al. 2013PASA...30...57J 2013PASA...30...57J);
JCO = CO from the JCMT archive
(http://www.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/en/jcmt/);
T13CO = 13CO from the ThrUMMS survey (The Three-mm Ultimate Mopra Milky Way
Survey; Barnes+ 2015ApJ...812....6B 2015ApJ...812....6B);
SMT = single-point observations using the Submillimeter Telescope (SMT).
Note (3): A "Y" indicates the clump is associated with extinction feature
at 70 micron.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- [CUS2014] Identifier
18- 21 F4.2 pc Req [0.05/4] Equivalent radii
23- 27 F5.2 K Tdust [10/25] Dust temperature
29- 36 E8.2 cm-2 NH2 H2 column density
38- 45 E8.2 cm-3 nH2 H2 number density
47- 50 F4.2 g/cm2 SigM [0.02/3] Mass surface density
52- 59 F8.2 Msun Mcl [7.7/61358] Clump mass
61- 69 F9.2 Lsun Lcl [8.6/140822] Clump luminosity
71- 75 F5.2 Lsun/Msun Lcl/Mcl [0.09/23] Ratio of clump luminosity to mass
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Aug-2017