J/ApJS/196/12 First results from Mopra HCO+ maps (Barnes+, 2011)
The Galactic census of high- and medium-mass protostars.
I. Catalogs and first results from Mopra HCO+ maps.
Barnes P.J., Yonekura Y., Fukui Y., Miller A.T., Muhlegger M., Agars L.C.,
Miyamoto Y., Furukawa N., Papadopoulos G., Jones S.L., Hernandez A.K.,
O'Dougherty S.N., Tan J.C.
<Astrophys. J. Suppl. Ser., 196, 12 (2011)>
=2011ApJS..196...12B 2011ApJS..196...12B
ADC_Keywords: Galactic plane ; Molecular clouds ; Interstellar medium ;
Velocity dispersion
Keywords: astrochemistry - ISM: kinematics and dynamics - ISM: molecules -
radio lines: ISM - stars: formation
Abstract:
The Census of High- and Medium-mass Protostars (CHaMP) is the first
large-scale, unbiased, uniform mapping survey at sub-parsec-scale
resolution of 90GHz line emission from massive molecular clumps in the
Milky Way. We present the first Mopra (ATNF) maps of the CHaMP survey
region (300°>l>280°) in the HCO+J=1->0 line, which is
usually thought to trace gas at densities up to 1011m-3. In this
paper, we introduce the survey and its strategy, describe the
observational and data reduction procedures, and give a complete
catalog of moment maps of the HCO+J=1->0 emission from the ensemble
of 303 massive molecular clumps. From these maps we also derive the
physical parameters of the clumps, using standard molecular
spectral-line analysis techniques.
Description:
CHaMP began with complete surveys of a large portion of the southern
Galactic Plane in four molecular spectral lines in the 3mm waveband
made with the 4m Nanten telescope (see Figure 1). A higher-resolution
follow-up campaign was then begun to map 209 clumps from the Nanten
Master Catalogue (NMC) in a number of 3mm molecular transitions with
the 22m diameter Mopra dish of the Australia Telescope National
Facility (ATNF) over the period 2004-2007, at much higher sensitivity
and angular resolution than with Nanten.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 43 209 Nanten Master Catalogue (NMC)
table4.dat 122 318 Mopra HCO+J=1->0 observed parameters
table5.dat 90 303 Mopra clump physical parameters (for Tex=10K)
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See also:
J/ApJS/195/14 : The Bolocam Galactic Plane Survey (BGPS). V. (Schlingman+,
2011)
J/PASJ/62/557 : CO clouds in the Galactic Center from NANTEN (Takeuchi+, 2010)
J/ApJ/707/283 : Ionized gas toward molecular clumps (Johnston+, 2009)
J/ApJS/182/131 : Molecular clouds and clumps in the GRS (Rathborne+, 2009)
http://www.astro.ufl.edu/~peterb/research/champ/ : The Galactic Census of
High and Medium-mass Protostars (CHaMP) home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- BYF [1/209] BYF number (<[BYF2011] NNN> in Simbad)
4 A1 --- f_BYF [*] *: Nanten clump that was mapped at Mopra
(see Table 4)
6- 13 F8.4 deg GLON Galactic longitude
15- 21 F7.4 deg GLAT Galactic latitude
23- 28 A6 --- Meth Method of clump identification (1)
30- 33 F4.2 K Tpk Peak temperature
35- 40 F6.2 km/s Vlsr LSR velocity
42- 43 A2 --- Reg Region (2)
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Note (1): Methods of clump identification are:
CF = from the CLUMPFIND program operating on the Nanten C18O data cube
(see Y. Yonekura et al. 2011, in preparation)
C18O = from visual inspection of the C18O Nanten data cube
HCO+ = from visual inspection of the HCO+ Nanten data cube
Note (2): Grouping of sources by Region is for convenience of mapping only;
see Figure 2 and Section 3.1. Some of these sources were too isolated
to be conveniently grouped into regions.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- BYF [1/209] BYF number
4 A1 --- m_BYF sub-clump letter (1)
6- 12 F7.3 deg GLON ? Galactic longitude
14- 19 F6.3 deg GLAT ? Galactic latitude
20 A1 --- f_BYF [N] N: no HCO+ emission could be discerned
in the Mopra data cubes at or near the
nominal NMC coordinates
22- 26 F5.2 K.km/s WHCO+ ? HCO+(J=1-0) integrated intensity
W(HCO+)=∫(T*RdV)
28- 31 F4.2 K.km/s e_WHCO+ ? rms uncertainty on WHCO+
33- 34 I2 --- NT* ? Noise level on WHCO+ (when no detection)
36- 40 F5.1 km/s bVel Lower velocity range
42- 47 F6.2 km/s BVel Upper velocity range
49- 52 F4.2 K Tp ? Peak brightness temperature
54- 57 F4.2 K e_Tp ? Tp uncertainty
59- 60 I2 --- NTp ? Noise level on Tp (when no detection)
62- 67 F6.2 km/s Vlsr ? LSR velocity
69- 72 F4.2 km/s e_Vlsr ? Vlsr uncertainty
74- 77 F4.2 km/s SigV ? Velocity dispersion
79- 82 F4.2 km/s e_SigV ? SigV uncertainty
84 A1 --- l_amaj Limit flag on amaj
85- 87 I3 arcsec amaj ? Major axis size
89- 90 I2 arcsec e_amaj ? amaj uncertainty
92 A1 --- l_bmin Limit flag on bmin
93- 95 I3 arcsec bmin ? Minor axis size
97- 98 I2 arcsec e_bmin ? bmin uncertainty
100-102 I3 deg PA ? Position angle
104 I1 deg e_PA ? PA uncertainty
106-108 F3.1 kpc Dcl Clump distance (2)
110-112 F3.1 kpc e_Dcl Dcl uncertainty
114-117 F4.2 kpc Dkn ? Near kinematic distance using Reid et al.
2009ApJ...700..137R 2009ApJ...700..137R
118 A1 --- --- [/]
119-122 F4.2 kpc Dkf ? Far kinematic distance using Reid et al.
2009ApJ...700..137R 2009ApJ...700..137R
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Note (1): Here we have added letter suffixes to the NMC catalog numbers to
indicate how the higher-resolution Mopra beam breaks up the emission
in the Nanten maps into smaller sub-clumps.
Note (2): Distances from the literature (Grabelsky et al. 1988ApJ...331..181G 1988ApJ...331..181G;
Yonekura et al. 2005ApJ...634..476Y 2005ApJ...634..476Y; Stolte et al.
2006AJ....132..253S 2006AJ....132..253S) using various classical optical or kinematic
methods (see Y. Yonekura et al. 2011, in preparation).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- BYF [1/209] BYF number
4 A1 --- m_BYF sub-clump letter
6- 8 F3.1 kpc Dist Final distance
9 A1 --- f_Dist [cnt] Flag on Dist (1)
11- 15 F5.3 --- tau Optical depth (τp)
17- 24 E8.3 m-2 Np Peak column density in HCO+
26- 31 F6.1 Msun/pc2 Sigp Mass surface density (2)
33- 36 F4.2 pc R Clump radius
38- 45 E8.3 m-3 ncol Estimated density at the emission peak
47- 52 F6.1 Msun/pc3 rcol Equivalent mass density (ρcol) (3)
54- 57 I4 Msun Mcol LTE mass
59- 64 F6.2 pPa Pgas Total gas pressure
66- 73 F8.4 K.pc2.km/s LHCO+ Peak line luminosity (4)
75- 79 F5.2 --- alpha Virial α parameter (α=Mvir/Mcol)
81- 84 F4.2 pc RJe Rayleigh-Jeans radius
86- 90 I5 Msun MBE Bonnor-Ebert mass
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Note (1): Distances taken from table 4 as follows:
c = literature-based value,
n = near kinematic,
t = tangent point
Note (2): Mass surface density as Σp=(Np/X)(µmolmH). Here, we
use an abundance X=10-9 for HCO+ relative to H2, which is our
best estimate from a number of studies. See section 4.3 for further
details.
Note (3): ρcol=µmolmHncol_, where µmol=2.30 is the mean
molecular mass in the gas. See section 4.4 for further details.
Note (4): The peak line luminosity L(HCO+)=W(HCO+)*d2θ2HPBW
where the Mopra effective telescope half-power beamwidth (HPBW) has
been smoothed at the gridding stage to 40".
See section 4.2 for futher details.
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History:
From electronic version of the journal
References:
Barnes et al. Paper I. 2011ApJS..196...12B 2011ApJS..196...12B This catalog
Ma et al. Paper II. 2013ApJ...779...79M 2013ApJ...779...79M Cat. J/ApJ/779/79
Barnes et al. Paper III. 2016ApJ...831...67B 2016ApJ...831...67B Cat. J/ApJ/831/67
(End) Emmanuelle Perret [CDS] 30-Dec-2011