J/ApJ/639/259 Sub-mm clumps in Orion B South molecular cloud (Johnstone+, 2006)
Large area mapping at 850 µm.
IV. Analysis of the clump distribution in the Orion B South molecular cloud.
Johnstone D., Matthews H., Mitchell G.F.
<Astrophys. J., 639, 259-274 (2006)>
=2006ApJ...639..259J 2006ApJ...639..259J
ADC_Keywords: Infrared sources ; Millimetric/submm sources ; Molecular clouds ;
Interstellar medium
Keywords: infrared: ISM - ISM: clouds -
ISM: individual (B33, NGC 2023, NGC 2024, Orion B South) -
ISM: structure - stars: formation
Abstract:
We present results from a survey of a 1300arcmin2 region of the
Orion B South molecular cloud, including NGC 2024, NGC 2023, and the
Horsehead Nebula (B33), obtained using the Submillimetre Common-User
Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT).
Submillimeter continuum observations at 450 and 850µm are
discussed. Using an automated algorithm, 57 discrete emission features
("clumps") are identified in the 850µm map.
Description:
The data covering Orion B South were obtained between 1997 and 2000
using SCUBA at the JCMT. The JCMT archive, hosted by the CADC was used
to find all relevant observations toward the region.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 73 57 Clump properties in Orion B South derived
from 850µm data
table2.dat 28 57 Submillimeter wavelength properties of clumps
in Orion B South
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See also:
J/ApJ/559/307 : Sub-mm mapping in Orion B molecular cloud (Johnstone+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- SMMJ Clump name (HHMMmm+DDMMm) (G1)
14- 15 I2 h RAh Hour of Right Ascension (J2000.0) (1)
17- 18 I2 min RAm Minute of Right Ascension (J2000.0) (1)
20- 23 F4.1 s RAs Second of Right Ascension (J2000.0) (1)
25 A1 --- DE- Sign of the Declination (J2000.0) (1)
26- 27 I2 deg DEd Degree of Declination (J2000.0) (1)
29- 30 I2 arcmin DEm Arcminute of Declination (J2000.0) (1)
32- 33 I2 arcsec DEs Arcsecond of Declination (J2000.0) (1)
35- 40 F6.2 Jy S850 Total flux density at 850µm (2)
42- 46 F5.2 Jy Sp850 Peak flux at 850µm, in units of Jy/beam (2)
48- 49 I2 10+3AU Reff Effective radius (2)
51- 54 F4.2 --- C Degree of concentration (3)
56- 57 I2 K Td Dust temperature (3)
59- 61 F3.1 [K/cm+3] log(P/k) Bounding pressure (3)
63- 67 F5.2 solMass M1 Mass derived from Bonnor-Ebert analysis (3)
69- 73 F5.2 solMass M2 Derived mass, assuming Td=20K (4)
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Note (1): Position of peak surface brightness within clump (accurate to 3").
Note (2): Radius, peak flux, and total flux are derived from clfind (Williams
et al. 1994, Cat. J/ApJ/428/693). The peak flux and total flux have
uncertainties of about 20%, mostly due to absolute flux calibration.
The radius has not been deconvolved from the telescope beam.
Note (3): Quantity derived from Bonnor-Ebert analysis.
Note (4): Mass derived from the total flux assuming Td=20K and
κ850=0.02cm2/g.
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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- 12 A12 --- SMMJ Clump name (HHMMmm+DDMMm) (G1)
14- 17 F4.1 --- FRt Total flux ratio (S450um/S850um) (1)
19- 22 F4.1 --- FRp Peak flux ratio (Sp450um/Sp850um) (1)
24- 25 I2 K Td1 Dust temperature derived from Bonnor-Ebert analysis
27- 28 I2 K Td2 Dust temperature derived from spectral energy
distribution (2)
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Note (1): The 850 and 450µm peak flux and total flux are derived from
CLFIND (Williams et al. 1994, Cat. J/ApJ/428/693) after
convolution to an identical beam size.
Note (2): Quantity derived from spectral energy fit to 450 and 850{um}m
integrated fluxes.
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Global Notes:
Note (G1): [JMM2006] SMM JHHMMmm+DDMMm in Simbad.
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History:
From electronic version of the journal
References:
Johnstone et al., Paper I 2000ApJS..131..505J 2000ApJS..131..505J
Johnstone et al., Paper II 2000ApJ...545..327J 2000ApJ...545..327J
Johnstone et al., Paper III 2001ApJ...559..307J 2001ApJ...559..307J, Cat. J/ApJ/559/307
(End) Marianne Brouty [CDS] 19-Jul-2007