J/MNRAS/468/250 SCUBA-2 Ambitious Sky Survey (Nettke+, 2017)
The SCUBA-2 Ambitious Sky Survey: a catalogue of beam-sized sources in the
Galactic longitude range 120°-140°.
Nettke W., Scott D., Gibb A.G., Thompson M., Chrysostomou A., Evans A.,
Hill T., Jenness T., Joncas G., Moore T., Serjeant S., Urquhart J.,
Vaccari M., Weferling B., White G., Zhu M.
<Mon. Not. R. Astron. Soc., 468, 250-260 (2017)>
=2017MNRAS.468..250N 2017MNRAS.468..250N (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Millimetric/submm sources ; Milky Way
Keywords: surveys - ISM: clouds - submillimetre: galaxies - submillimetre: ISM -
submillimetre: stars
Abstract:
The SCUBA-2 Ambitious Sky Survey (SASSy) is composed of shallow
850-µm imaging using the Submillimetre Common-User Bolometer Array
2 (SCUBA-2) on the James Clerk Maxwell Telescope. Here we describe the
extraction of a catalogue of beam-sized sources from a roughly
120deg2 region of the Galactic plane mapped uniformly (to an rms
level of about 40mJy), covering longitude 120°<l<140° and
latitude |b|<2.9°. We used a matched-filtering approach to
increase the signal-to-noise ratio (S/N) in these noisy maps and
tested the efficiency of our extraction procedure through estimates of
the false discovery rate, as well as by adding artificial sources to
the real images. The primary catalogue contains a total of 189 sources
at 850µm, down to an S/N threshold of approximately 4.6.
Additionally, we list 136 sources detected down to S/N=4.3, but
recognize that as we go lower in S/N, the reliability of the catalogue
rapidly diminishes. We perform follow-up observations of some of our
lower significance sources through small targeted SCUBA-2 images and
list 265 sources detected in these maps down to S/N=5. This
illustrates the real power of SASSy: inspecting the shallow maps for
regions of 850-µm emission and then using deeper targeted images to
efficiently find fainter sources. We also perform a comparison of the
SASSy sources with the Planck Catalogue of Compact Sources and the
IRAS Point Source Catalogue, to determine which sources discovered in
this field might be new, and hence potentially cold regions at an
early stage of star formation.
Description:
This beam-sized source catalogue is based on scans of Scuba-2 imagery
obtained between 2012 May 15 and 2014 May 12 using the James Clerk
Maxwell Telescope. There are three catalogues as well as one PDF file
which details a source comparison of samples from each catalogue.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
primary.dat 92 189 The Primary catalogue (Table 2)
suppl.dat 92 136 The Supplementary catalogue (Table 3)
daisy.dat 83 265 The DAISY Catalogue (Table 5)
comparison.pdf 512 514 Source comparison of samples
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See also:
J/MNRAS/458/4321 : SCUBA-2 galaxies in 850um survey (Koprowski+, 2016)
Byte-by-byte Description of file: primary.dat suppl.dat
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Bytes Format Units Label Explanations
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1- 25 A25 --- Name Source name, JCMTLSYP LLL.llll+B.bbbb
27- 29 I3 --- ID [1/325] Source ID
31- 38 F8.4 deg GLON Galactic Longitude
40- 46 F7.4 deg GLAT Galactic Latitude
48- 49 I2 h RAh Right Ascension (J2000)
51- 52 I2 min RAm Right Ascension (J2000)
54- 57 F4.1 s RAs Right Ascension (J2000)
58 A1 --- DE- Declination sign (J2000)
59- 60 I2 deg DEd Declination (J2000)
62- 63 I2 arcmin DEm Declination (J2000)
65- 66 I2 arcsec DEs Declination (J2000)
68- 72 F5.1 --- S/N Signal-to-Noise reading
74- 78 I5 mJy S850 Source Flux at 850-micron band
80 A1 --- l_S450 Lower limit flag on S450
81- 85 I5 mJy S450 Source Flux at 450-micron band
87- 92 A6 --- Flag Flag indicating if the source has some
defining characteristic we want to mark as
relevant to this work (1)
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Note (1): Flag as follows:
E = if a source is most likely part of a larger structure of emission, broken
up by our matched-filter approach. The criterion for a source to be
labelled this way is whether or not the nearest source peak lies within
48 arcsec for pong maps and 42 arcsec for daisy maps
∼P = if a source was not matched in the Planck catalogue
∼I = if a source was not matched in the IRAS catalogue
D = if a source that was followed up by a daisy observation was confirmed
to be real
∼D = if a source was undetected in a follow-up daisy observation
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Byte-by-byte Description of file: daisy.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 24 A24 --- Name Source Name, JCMTLSYP LLL.llll+B.bbbb
26- 29 A4 --- ID Source ID (1D-265D)
31- 38 F8.4 deg GLON Galactic Longitude
40- 46 F7.4 deg GLAT Galactic Latitude
48- 49 I2 h RAh Right Ascension (J2000)
51- 52 I2 min RAm Right Ascension (J2000)
54- 57 F4.1 s RAs Right Ascension (J2000)
58 A1 --- DE- Declination sign (J2000)
59- 60 I2 deg DEd Declination (J2000)
62- 63 I2 arcmin DEm Declination (J2000)
65- 66 I2 arcsec DEs Declination (J2000)
68- 72 F5.1 --- S/N Signal-to-Noise reading
74- 81 F8.2 mJy S850 Source Flux at 850-micron band
83 A1 --- Flag [E] Flag indicating if the source has some
defining characteristic we want to mark as
relevant to this work (1)
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Note (1): E = indicating if the source appears to be part of a larger emission
structure that was broken up by the matched filter.
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History:
From electronic version of the journal
Will Nettke, willnettke(at)gmail.com
(End) W. Nettke [Univ. of British Columbia], P. Vannier [CDS] 22-Mar-2020