J/ApJS/195/14 The Bolocam Galactic Plane Survey (BGPS). V. (Schlingman+, 2011)
The Bolocam Galactic Plane Survey.
V. HCO+ and N2H+ spectroscopy of 1.1 mm dust continuum sources.
Schlingman W.M., Shirley Y.L., Schenk D.E., Rosolowsky E., Bally J.,
Battersby C., Dunham M.K., Ellsworth-Bowers T.P., Evans II N.J.,
Ginsburg A., Stringfellow G.
<Astrophys. J. Suppl. Ser., 195, 14 (2011)>
=2011ApJS..195...14S 2011ApJS..195...14S
ADC_Keywords: Spectra, millimetric/submm ; Surveys ; Interstellar medium
Keywords: Galaxy: kinematics and dynamics - Galaxy: structure - ISM: clouds -
ISM: kinematics and dynamics - stars: formation - submillimeter: ISM -
surveys
Abstract:
We present the results of observations of 1882 sources in the Bolocam
Galactic Plane Survey (BGPS) at 1.1mm with the 10m Henrich Hertz
Telescope simultaneously in HCO+J=3-2 and N2H+J=3-2. We detect
77% of these sources in HCO+ and 51% in N2H+ at greater than
3σ. We find a strong correlation between the integrated
intensity of both dense gas tracers and the 1.1mm dust emission of
BGPS sources. We determine kinematic distances for 529 sources (440 in
the first quadrant breaking the distance ambiguity and 89 in the
second quadrant). We derive the size, mass, and average density for
this subset of clumps. The median size of BGPS clumps is 0.75pc with a
median mass of 330M☉ (assuming TDust=20K). BGPS clumps
represent a wide range of objects (from dense cores to more diffuse
clumps) and are typically characterized by larger sizes and lower
densities than previously published surveys of high-mass star-forming
regions.
Description:
Observations were conducted with HHT on Mount Graham, Arizona. The
data were taken over the course of 44 nights beginning in 2009
February and ending in 2009 June. We selected sources out of a
preliminary version of the BGPS source catalog (BOLOCAT;
Rosolowsky et al. 2010, Cat. J/ApJS/188/123).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 178 1882 Results of HCO+ and N2H+ spectroscopy
table5.dat 98 529 Table of computed quantities
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See also:
J/ApJS/188/123 : The Bolocam Galactic Plane Survey. II. (Rosolowsky+, 2010)
J/ApJ/638/293 : 1.1mm sources in the Perseus Molecular Cloud (Enoch+, 2006)
J/ApJ/582/756 : Velocities of HII regions (Kolpak+, 2003)
http://irsa.ipac.caltech.edu/data/BOLOCAM_GPS/ : The Bolocam GPS archive
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- BGPS BGPS name (Bolocam Galactic Plane Survey)
17- 18 I2 h RAh Hour of Right Ascension (J2000)
20- 21 I2 min RAm Minute of Right Ascension (J2000)
23- 26 F4.1 s RAs Second of Right Ascension (J2000)
28 A1 --- DE- Sign of the Declination (J2000)
29- 30 I2 deg DEd Degree of Declination (J2000)
32- 33 I2 arcmin DEm Arcminute of Declination (J2000)
35- 38 F4.1 arcsec DEs Arcsecond of Declination (J2000)
40- 46 F7.3 deg GLON Galactic longitude
48- 53 F6.3 deg GLAT Galactic latitude
55- 60 F6.1 arcsec Offset Offset to v1.0
62- 67 F6.3 Jy F1.1 The 1.1mm flux density; Jy/beam
69- 73 F5.3 Jy e_F1.1 ? Uncertainty in F1.1; Jy/beam
76 I1 --- n_THCO ?=0 HCO+ line flag (3)
78- 83 F6.3 K THCO ? The HCO+ beam temperature
85- 89 F5.3 K e_THCO ? Uncertainty in THCO (1)
91- 97 F7.3 K.km/s IHCO ? The HCO+ intensity
99-103 F5.3 K.km/s e_IHCO ? Uncertainty in IHCO (1)
105-110 F6.3 km/s WHCO ? The HCO+ FWHM
111 A1 --- f_WHCO [N] N: Indicates a "NaN" value for WHCO (2)
113-119 F7.3 km/s VHCO ? The HCO+ local standard of rest velocity
121 I1 --- n_TN2H ?=0 N2H+ line flag (3)
123-127 F5.3 K TN2H ? The N2H+ beam temperature
129-133 F5.3 K e_TN2H Uncertainty in TN2H (1)
135-140 F6.3 K.km/s IN2H ? The N2H+ intensity
142-146 F5.3 K.km/s e_IN2H Uncertainty in IN2H (1)
148-153 F6.3 km/s WN2H ? The N2H+ FWHM
155-161 F7.3 km/s VN2H ? The N2H+ local standard of rest velocity
163-168 F6.4 kpc Dnear ? Near kinematic distance
170-176 F7.4 kpc Dfar ? Far kinematic distance
178 I1 --- n_Dfar ?=0 Reference for distance estimation (G1)
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Note (1): For entries with no measured line, the flux value is blank but
the error on the baseline is provided.
Note (2): The measured linewidth is less than the channel width.
The upper limit is 1.12km/s.
Note (3): Line flags as follows (table2 of paper):
0 = No detection: there is no visible line
1 = Single detection: one line visible with no visible structure
2 = Multiple detections: more than one line is visible in the spectrum
4 = Obvious line wings: one line that shows a possible line wing(s)
5 = Self-absorbed profile: one line that shows a possible
self-absorbed profile
9 = Unusable data: both polarizations have defects that make
the spectrum unusable
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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- 15 A15 --- BGPS BGPS name (1)
17- 23 F7.3 deg GLON Galactic longitude
25- 30 F6.3 deg GLAT Galactic latitude
32- 37 F6.3 Jy F1.1 The 1.1mm flux density (in Jy/beam)
39- 40 I2 --- Dflg [1/13] Reference for distance estimation (G1)
42- 46 I5 Msun Mass Estimated Mass
48- 53 F6.3 km/s WHCO The HCO+ FWHM
55- 61 F7.3 --- alpha Virial parameter α (2)
63- 70 F8.1 cm-3 <BDen> Beam averaged density
72- 78 F7.1 cm-3 <VDen> Volume averaged density
80- 84 F5.3 g/cm2 SDen Mass surface density Σ
86- 91 F6.3 10+5yr t(ff) Clump free fall timescale
93- 98 F6.3 10+5yr t(cc) Clump crossing timescale
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Note (1): Calculated quantities in this table assume Td=20K for all sources.
Note (2): the virial parameter α is defined by
α=5Δv2/8ln(2πGΣR), where
v = observed velocity,
Σ = mass surface density,
R = galactocentric distance.
A value α<1 indicates a gravitationally bound clump.
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Global notes:
Note (G1): Flag as follows:
1 = Parallax;
2 = Infrared Dark Cloud (IRDC) Coincidence;
3 = Kolpak et al. (2003, Cat. J/ApJ/582/756);
4 = Shirley et al. (2003ApJS..149..375S 2003ApJS..149..375S);
5 = Tangent Distance;
6 = Outer Galaxy;
7 = W3/4/5 Region;
8 = NGC 7538 Region;
9 = Cygnus X Region;
10 = Outer Arm (Cyg X);
11 = IC1396;
12 = 3kpc Arm;
13 = Outer Arm.
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History:
* 19-Sep-2011: From electronic version of the journal
* 01-Dec-2011: Note on the HCO/N2H detection fixed, as note (3)
of table3 (thanks to a remark from a co-author)
References:
Aguirre et al. Paper I. 2011ApJS..192....4A 2011ApJS..192....4A
Rosolowsky et al. Paper II. 2010ApJS..188..123R 2010ApJS..188..123R Cat. J/ApJS/188/123
Dunham et al. Paper III. 2010ApJ...717.1157D 2010ApJ...717.1157D
Bally et al. Paper IV. 2010ApJ...721..137B 2010ApJ...721..137B Cat. J/ApJ/721/137
Schlingman et al. Paper V. 2011ApJS..195...14S 2011ApJS..195...14S Cat. J/ApJS/195/14
Dunham et al. Paper VII. 2011ApJ...741..110D 2011ApJ...741..110D Cat. J/ApJ/741/110
Ellsworth-Bowers et al. Paper VIII. 2013ApJ...770...39E 2013ApJ...770...39E
Ginsburg et al. Paper IX. 2013ApJS..208...14G 2013ApJS..208...14G
Shirley et al. Paper X. 2013ApJS..209....2S 2013ApJS..209....2S Cat. J/ApJS/209/2
Merello et al. Paper XI. 2015ApJS..218....1M 2015ApJS..218....1M Cat. J/ApJS/218/1
Ellsworth-Bowers et al. Paper XII. 2015ApJ...799...29E 2015ApJ...799...29E Cat. J/ApJ/799/29
Ellsworth-Bowers et al. Paper XIII. 2015ApJ...805..157E 2015ApJ...805..157E Cat. J/ApJ/805/157
Svoboda et al. Paper XIV. 2016ApJ...822...59S 2016ApJ...822...59S Cat. J/ApJ/822/59
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 19-Sep-2011