J/ApJS/247/29 CO obs. of Planck Galactic cold clumps (Zhang+, 2020)
Planck Galactic cold clumps in two regions: the first quadrant and the
anticenter direction region.
Zhang C., Wu Y., Liu X., Qin S.-L., Liu T., Yuan J., Li D., Meng F.,
Zhang T., Tang M., Yuan L., Zhou C., Esimbek J., Zhou Y., Chen P., Hu R.
<Astrophys. J. Suppl. Ser., 247, 29 (2020)>
=2020ApJS..247...29Z 2020ApJS..247...29Z
ADC_Keywords: Interstellar medium; Millimetric/submm sources; Molecular clouds;
Carbon monoxide; Star Forming Region; Velocity dispersion
Keywords: Dark interstellar clouds ; Interstellar molecules ; Star formation
Abstract:
Sixty-five Planck Galactic cold clumps (PGCCs) from the first quadrant
(IQuad) and 39 from the anticenter direction region (ACent) were
observed in 12CO, 13CO, and C18O J=1-0 lines using the 13.7m
telescope of the Purple Mountain Observatory. All the targets were
detected in all three lines, except for 12 IQuad and 8 ACent PGCCs
without C18O detection. Seventy-six and 49 velocity components were
obtained in IQuad and ACent respectively; 146 cores were extracted
from 76 IQuad clumps and 100 cores from 49 ACent clumps. The average
Tex of IQuad cores and ACent cores is 12.4K and 12.1K, respectively.
The average line widths of 13CO of IQuad cores and ACent cores are
1.55km/s and 1.77km/s, respectively. Among the detected cores, 24 in
IQuad and 13 in ACent have asymmetric line profiles. The small blue
excesses, ∼0.03 in IQuad and 0.01 in ACent, indicate that star
formation is not active in these PGCC cores. Power-law fittings of the
core mass function to the high-mass end give indices of -0.57 in IQuad
and -1.02 in ACent, which are flatter than the slope of the initial
mass function given by Salpeter. The large turnover masses of
28M☉ for IQuad cores and 77M☉ for ACent cores suggest low
star formation efficiencies in PGCCs. The correlation between virial
mass and gas mass indicates that most PGCC cores in both regions are
not likely pressure-confined.
Description:
The sample in this paper is a subset of 674 Planck Galactic cold
clumps (PGCCs) observed by Wu+ (2012 J/ApJ/756/76) located in the
first quadrant (IQuad) and the anticenter direction region (ACent),
selected from the Early Cold Cores (ECC) catalog (Planck
Collaboration, 2011, VIII/88).
Observations of the 65 IQuad PGCCs and 39 ACent PGCCs were carried out
with the 13.7m millimeter-wavelength telescope of the Purple Mountain
Observatory (PMO) in the J=1-0 transition of 12CO, 13CO, and C18O
from 2011 April to May and from 2011 December to 2012 January.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 112 104 Sample of Planck Galactic cold clumps (PGCCs)
table2.dat 127 246 Line parameters of core centers
table4.dat 79 246 Derived parameters at the core center
table6.dat 68 246 Emission region parameters
table9.dat 28 58 *Fifty-eight cores associated with objects
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Note on table9.dat: We have matched clumps with the Class I/II YSO candidates
and the Class III YSO candidates from Marton+ 2016, J/MNRAS/458/3479 and
IRAS point source catalog (Helou & Walker 1988, II/125).
An objects is believed to be associated with a core if it has an
offset to the core center of less than a beam size (∼1') and a
distance (if we can get it from the catalogs) similar to the core.
See Section 4.5.3.
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See also:
II/125 : IRAS cat. of Point Sources, Version 2.0 (IPAC 1986)
VIII/39 : Composite CO Survey of the Milky Way (Dame+ 1987)
II/249 : WHAM Northern Sky Survey, V-1.1 (Haffner+, 2003)
J/ApJ/428/693 : Rosette Nebula & Maddalena Cloud structures (Williams+ 1994)
J/ApJS/125/161 : A database of dense cores mapped in ammonia (Jijina+, 1999)
J/A+A/462/L17 : Dense cores in interstellar molecular clouds (Alves+, 2007)
J/MNRAS/374/1413 : SCUBA survey of Orion (Nutter+, 2007)
J/MNRAS/391/869 : A mapping survey of massive CO cores (Guan+, 2008)
J/A+A/487/993 : MAMBO Mapping of c2d Clouds and Cores (Kauffmann+, 2008)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/ApJ/691/1560 : Dense core survey in the Orion B cloud (Ikeda+, 2009)
J/ApJ/712/797 : YSOs in Vul OB1 association (Billot+, 2010)
J/ApJS/202/4 : Planck cold clumps survey in the Orion complex (Liu+, 2012)
J/ApJ/756/76 : Planck cold dust clumps CO survey (Wu+, 2012)
J/ApJS/209/37 : Planck cold clumps in 12CO, 13CO & C18O (Meng+, 2013)
J/ApJ/794/124 : NGC 2264 Spitzer sources (Rapson+, 2014)
J/A+A/584/A93 : Galactic cold cores. V. Dust opacity (Juvela+, 2015)
J/A+A/584/A91 : Dense cores in Aquila from Herschel (Konyves+, 2015)
J/MNRAS/458/3027 : Young and embedded clusters in Cygnus-X (Maia+, 2016)
J/MNRAS/458/3479 : SVM selection of WISE YSO Candidates (Marton+, 2016)
J/A+A/594/A28 : Planck Cat. of Galactic cold clumps (PGCC) (Planck+, 2016)
J/MNRAS/463/1008 : LDN 1495 SCUBA-2 and Herschel data (Ward-Thompson+, 2016)
J/ApJ/820/37 : HCO+ & HCN obs. toward PGCCs (Yuan+, 2016)
J/ApJS/224/43 : Planck cold clumps & cores in 2nd quadrant (Zhang+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Quad Quadrant ("IQuad": first Galactic quadrant or
"ACent": Galactic anti-center direction region)
7- 19 A13 --- Clump Clump
21- 30 F10.6 deg GLON [13.86/226.81] Galactic longitude
32- 42 F11.8 deg GLAT [-9.7/10.81] Galactic latitude
44- 45 I2 h RAh [5/22] Hour of Right Ascension (J2000)
47- 48 I2 min RAm Minute of Right Ascension (J2000)
50- 54 F5.2 s RAs Second of Right Ascension (J2000)
56- 56 A1 --- DE- Sign of the Declination (J2000)
57- 58 I2 deg DEd Degree of Declination (J2000)
60- 61 I2 arcmin DEm Arcminute of Declination (J2000)
63- 67 F5.2 arcsec DEs Arcsecond of Declination (J2000)
69- 70 I2 h RABh [5/22] Hour of Right Ascension (B1950)
72- 73 I2 min RABm Minute of Right Ascension (B1950)
75- 79 F5.2 s RABs Second of Right Ascension (B1950)
81- 81 A1 --- DEB- Sign of the Declination (B1950)
82- 83 I2 deg DEBd Degree of Declination (B1950)
85- 86 I2 arcmin DEBm Arcminute of Declination (B1950)
88- 92 F5.2 arcsec DEBs Arcsecond of Declination (B1950)
94-104 A11 --- Region Sub-region (1)
106-112 A7 --- OB OB association (2)
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Note (1): The limits of the sub-regions are from Dame+ (1987, VIII/39)
and Humphreys (1978ApJS...38..309H 1978ApJS...38..309H).
Note (2): The limits of the OB associations are
from Humphreys (1978ApJS...38..309H 1978ApJS...38..309H).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Clump Clump
14 A1 --- m_Clump [a-d] Component identifier in Clump
15- 16 A2 --- Core [C1-5] Core identifier in Clump
18- 21 F4.2 kpc Dist [0.2/9.2]? Distance
23- 27 F5.2 K Tb-12CO [3.9/19.1] 12CO brightness temperature
29- 32 F4.2 K e_Tb-12CO [0.07/2.8] Uncertainty in Tb-12CO
34- 38 F5.2 km/s Vlsr-12CO [-7.5/46.2] LSR (centroid) velocity, 12CO
40- 43 F4.2 km/s e_Vlsr-12CO [0.01/0.2] Uncertainty in Vlsr-12CO
45- 48 F4.2 km/s dV-12CO [0.6/6.5] Line width, FWHM, 12CO
50- 53 F4.2 km/s e_dV-12CO [0.01/0.4] Uncertainty in dV-12CO
55- 58 F4.2 K Tb-13CO [0.6/9.4] 13CO brightness temperature
60- 63 F4.2 K e_Tb-13CO [0.05/1.3] Uncertainty in Tb-13CO
65- 69 F5.2 km/s Vlsr-13CO [-7.3/46.3] LSR (centroid) velocity, 13CO
71- 74 F4.2 km/s e_Vlsr-13CO [0/0.2] Uncertainty in Vlsr-13CO
76- 79 F4.2 km/s dV-13CO [0.4/5.2] Line width, FWHM, 13CO
81- 84 F4.2 km/s e_dV-13CO [0.01/0.4] Uncertainty in dV-13CO
86- 89 F4.2 K Tb-C18O [0.3/3.4]? C18O brightness temperature
91- 94 F4.2 K e_Tb-C18O [0.06/6.6]? Uncertainty in Tb-C18O
96-100 F5.2 km/s Vlsr-C18O [-5.6/29.1]? LSR (centroid) velocity, C18O
102-105 F4.2 km/s e_Vlsr-C18O [0.01/0.3]? Uncertainty in Vlsr-C18O
107-110 F4.2 km/s dV-C18O [0.17/4]? Line width, FWHM, C18O
112-115 F4.2 km/s e_dV-C18O [0.02/0.8]? Uncertainty in dV-C18O
117-121 F5.2 km/s V-peak [-7.3/48] Peak velocity, 12CO
123-127 A5 --- Profile Profile (1)
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Note (1): Profiles as follows:
RA = red asymmetry;
BA = blue asymmetry;
RP = red profile;
BP = blue profile;
wings = wings.
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Clump Clump
14 A1 --- m_Clump [a-d] Component identifier in Clump
15- 16 A2 --- Core [C1-5] Core identifier in Clump
18- 22 F5.2 K Tex [7.2/22.5] Excitation temperature
24- 27 F4.2 K e_Tex [1/1.1] Uncertainty in Tex
29- 32 F4.2 --- tau-13CO [0.07/3.8] optical depth, 13CO
34- 37 F4.2 --- e_tau-13CO [0.01/3.2] Uncertainty in tau-13CO
39- 43 F5.2 10+21cm-1 NH2 [0.5/68.7] H2 column density
45- 49 F5.2 10+21cm-1 e_NH2 [0.2/26.7] Uncertainty in NH2
51- 54 F4.2 km/s sigma-NT [0.1/2.2] Non-thermal velocity dispersion,
σNT
56- 59 F4.2 km/s e_sigma-NT [0.01/0.07] Uncertainty in sigma-NT
61- 64 F4.2 km/s sigma-Th [0.1/0.3] Thermal velocity dispersion,
σTh
66- 69 F4.2 km/s e_sigma-Th [0.01] Uncertainty in sigma-Th
71- 74 F4.2 km/s sigma-3D [0.4/4] Three-dimensional velocity
dispersion, σ3D
76- 79 F4.2 km/s e_sigma-3D [0.01/0.2] Uncertainty in sigma-3D
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Clump Clump
14 A1 --- m_Clump [a-d] Component identifier in Clump
15- 16 A2 --- Core [C1-5] Core identifier in Clump
18- 21 I4 arcsec oRA [-396/361] Offset, Right Ascension
23- 26 I4 arcsec oDE [-385/355] Offset, Declination
28- 30 I3 arcsec amaj [99/435] semi-major axis, Gaussian fit
32- 34 I3 arcsec bmin [60/300] semi-minor axis, Gaussian fit
36- 39 F4.2 pc Rad [0.04/2.94] Radius
41- 45 F5.2 10+3cm-3 n3 [0.34/21.65] Volume particle density
47- 52 F6.1 Msun Mcore [0.1/7612.8] Core mass
54- 57 I4 Msun Mvir [3/3300] Virial mass
59- 62 I4 Msun MJeans [4/3121] Jeans mass
64- 68 F5.2 --- aVir [0.16/52.51] Virial parameter, α
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Byte-by-byte Description of file: table9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Quad Quadrant ("IQuad": first Galactic quadrant or
"ACent": Galactic anti-center direction region)
7- 19 A13 --- Clump Clump
20 A1 --- m_Clump [abd] Component identifier in Clump
21- 22 A2 --- Core [C1-5] Core identifier in Clump
24 I1 --- I/II Class I/II YSO candidate
26 I1 --- III Class III YSO candidate
28 I1 --- IRAS IRAS point source
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Jun-2020