J/MNRAS/463/1008 LDN 1495 SCUBA-2 and Herschel data (Ward-Thompson+, 2016)
The JCMT and Herschel Gould Belt Surveys: a comparison of SCUBA-2 and
Herschel data of dense cores in the Taurus dark cloud L1495.
Ward-thompson D., Pattle K., Kirk J.M., Marsh K., Buckle J., Hatchell J.,
Nutter D.J., Griffin M.J., Di Francesco J., Andre P., Beaulieu S.,
Berry D., Broekhoven-Fiene H., Currie M., Fich M., Jenness T.,
Johnstone D., Kirk H., Mottram J., Pineda J., Quinn C., Sadavoy S.,
Salji C., Tisi S., Walker-Smith S., White G., Hill T., Konyves V.,
Palmeirim P., Pezzuto S.
<Mon. Not. R. Astron. Soc., 463, 1008-1025 (2016)>
=2016MNRAS.463.1008W 2016MNRAS.463.1008W (SIMBAD/NED BibCode)
ADC_Keywords: Molecular clouds ; Photometry, millimetric/submm
Keywords: stars: formation; ISM: clouds -
ISM: Individual objects: Taurus and L1495
Abstract:
We present a comparison of Submillimetre Common User Bolometer Array-2
(SCUBA-2) 850-µm and Herschel 70-500-µm observations of the
L1495 filament in the Taurus Molecular Cloud with the goal of
characterizing the SCUBA-2 Gould Belt Survey (GBS) data set. We
identify and characterize starless cores in three data sets: SCUBA-2
850-µm, Herschel 250-µm, and Herschel 250-µm spatially
filtered to mimic the SCUBA-2 data. SCUBA-2 detects only the
highest-surface-brightness sources, principally detecting protostellar
sources and starless cores embedded in filaments, while Herschel is
sensitive to most of the cloud structure, including extended
low-surface-brightness emission. Herschel detects considerably more
sources than SCUBA-2 even after spatial filtering. We investigate
which properties of a starless core detected by Herschel determine its
detectability by SCUBA-2, and find that they are the core's
temperature and column density (for given dust properties). For
similar-temperature cores, such as those seen in L1495, the surface
brightnesses of the cores are determined by their column densities,
with the highest-column-density cores being detected by SCUBA-2. For
roughly spherical geometries, column density corresponds to volume
density, and so SCUBA-2 selects the densest cores from a population at
a given temperature. This selection effect, which we quantify as a
function of distance, makes SCUBA-2 ideal for identifying those cores
in Herschel catalogues that are closest to forming stars. Our results
can now be used by anyone wishing to use the SCUBA-2 GBS data set.
Description:
The L1495 region of the Taurus molecular cloud was observed with the
SCUBA-2 camera in 22 observations taken between October 2011 and July
2013.
The comparison Herschel data used in this paper were taken as part of
the Herschel Gould Belt Survey (Andre et al. 2010A&A...518L.102A 2010A&A...518L.102A) and
were presented by Marsh et al. (2016MNRAS.459..342M 2016MNRAS.459..342M, Cat.
J/MNRAS/459/342). They were taken simultaneously with the
Photodetector Array Camera and Spectrometer, PACS and the Spectral and
Photometric Imaging Receiver, SPIRE using the combined fast-scanning
(60 arcsec/s) SPIRE/PACS parallel mode.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 80 25 Sources found by the CSAR algorithm in its
non-hierarchical mode in the 850-um SCUBA-2 data
table2.dat 44 25 Derived properties of the sources found by
SCUBA-2 in the L1495 region
tablea1.dat 79 208 CSAR output for Herschel sources
tablea2.dat 80 138 CSAR output for filtered-Herschel sources
tablea3.dat 44 208 Derived properties of Herschel sources
tablea4.dat 44 138 Derived properties of filtered-Herschel sources
tableb1.dat 52 42 Sources detected in increased-noise filtered
Herschel 250-um data
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See also:
J/A+A/574/A104 : Dense cores in L1495/B213 complex (Tafalla+, 2015)
J/MNRAS/459/342 : Dense cores in Taurus L1495 cloud (Marsh+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Source Source designation (SNN) (1)
5 I1 h RAh Rigth ascension (J2000)
7- 8 I2 min RAm Rigth ascension (J2000)
10- 14 F5.2 s RAs Rigth ascension (J2000)
16 A1 --- DE- Declination sign (J2000)
17- 18 I2 deg DEd Declination (J2000)
20- 21 I2 arcmin DEm Declination (J2000)
23- 26 F4.1 arcsec DEs Declination (J2000)
28- 31 F4.1 arcsec FWHM1 Size
32 A1 --- --- [x]
33- 36 F4.1 arcsec FWHM2 Size
38- 42 F5.1 deg Angle Position angle (E of N)
44- 48 F5.2 Jy F160 Total 160um flux
50- 54 F5.2 Jy F250 Total 250um flux
56- 60 F5.2 Jy F350 Total 350um flux
62- 66 F5.2 Jy F500 Total 500um flux
68- 71 F4.2 Jy F850 Total 850um flux
73- 75 A3 --- CtpH Herschel counterpart source
76 A1 --- --- [,]
78- 80 A3 --- CtpF Filtered-Herschel counterpart source
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Note (1): Sources labelled 'S', listed in this table, are detected in SCUBA-2
850um emission.
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Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Source Source designation
(HNNN for tablea1, FNN for tablea2)
6 I1 h RAh Rigth ascension (J2000)
8- 9 I2 min RAm Rigth ascension (J2000)
11- 15 F5.2 s RAs Rigth ascension (J2000)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 33 F5.1 arcsec FWHM1 Size
34 A1 --- --- [x]
35- 38 F4.1 arcsec FWHM2 Size
40- 44 F5.1 deg Angle Position angle (E of N)
46- 50 F5.2 Jy F160 Total 160um flux
52- 56 F5.2 Jy F250 Total 250um flux
58- 62 F5.2 Jy F350 Total 350um flux
64- 68 F5.2 Jy F500 Total 500um flux
70 A1 --- --- [(]
71- 74 F4.2 Jy F850 Extrapolate total 850um flux
75 A1 --- --- [)]
77- 80 A4 --- Ctp ? Counterpart Marsh (tablea1, NNN) or
Herschel (tablea2, HNN) source (1)
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Note (1): in tablea1, counterpart sources in Marsh et al., 2016,
Cat. J/MNRAS/459/342, [MKA2016] NNN in Simbad.
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Byte-by-byte Description of file: table2.dat tablea3.dat tablea4.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Source Source designation (SNN for table2,
HNNN for tablea3, FNNN for tablea4)
6- 10 F5.1 K T Temperature
12- 14 F3.1 K e_T rms uncertainty on temperature
16- 20 F5.3 Msun Mass Mass
22- 26 F5.3 Msun e_Mass rms uncertainty on mass
28- 32 F5.2 10+4cm3 Dens Density
34- 38 F5.2 10+4cm3 e_Dens rms uncertainty on density
40- 44 F5.3 pc Deconv Deconvoled FWHM
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Source Source designation (Nnn)
6 I1 h RAh Rigth ascension (J2000)
8- 9 I2 min RAm Rigth ascension (J2000)
11- 15 F5.2 s RAs Rigth ascension (J2000)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 32 F4.1 arcsec FWHM1 Size
33 A1 --- --- [x]
34- 37 F4.1 arcsec FWHM2 Size
39- 43 F5.1 deg Angle Position angle (E of N)
45- 47 A3 --- CtpS SCUBA-2 850um emission detected
counterpart source
48 A1 --- --- [,]
50- 52 A3 --- CtpF Filtered-Herschel counterpart source
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 02-May-2018