J/ApJS/175/277 Submillimeter-Continuum SCUBA detections (Di Francesco+, 2008)
The SCUBA legacy catalogues: submillimeter-continuum objects detected by SCUBA.
Di Francesco J., Johnstone D., Kirk H., MacKenzie T., Ledwosinska E.
<Astrophys. J. Suppl. Ser., 175, 277-295 (2008)>
=2008ApJS..175..277D 2008ApJS..175..277D
ADC_Keywords: Millimetric/submm sources ; Atlases
Keywords: atlases - catalogs - submillimeter - techniques: image processing
Abstract:
We present the SCUBA Legacy Catalogues, two comprehensive sets of
continuum maps (and catalogs) using data at 850 and 450um of the
various astronomical objects obtained with the Submillimetre Common
User Bolometer Array (SCUBA). The Fundamental Map Data Set contains
data only where superior atmospheric opacity calibration data were
available. The Extended Map Data Set contains data regardless of the
quality of the opacity calibration. Each data set contains
1.2°x1.2° maps at locations where data existed in the JCMT
archive, imaged using the matrix inversion method. The Fundamental
Data Set is composed of 1423 maps at 850um and 1357 maps at 450um.
The Extended Data Set is composed of 1547 maps at 850um. Neither data
set includes high sensitivity, single-chop SCUBA maps of "cosmological
fields" nor solar system objects. Each data set was used to determine
a respective object catalogue, consisting of objects identified within
the respective 850um maps using an automated identification algorithm.
The Fundamental and Extended Map Object Catalogues contain 5061 and
6118 objects, respectively. Objects are named based on their
respective J2000.0 position of peak 850um intensity. The catalogues
provide for each object the respective maximum 850um intensity,
estimates of total 850um flux and size, and tentative identifications
from the SIMBAD Database. Where possible, the catalogues also provide
for each object its maximum 450um intensity and total 450um flux and
flux ratios.
Description:
Since the goal of this project was to make maps and then catalog
objects therein, all raw jiggle and scan data from SCUBA available in
the JCMT archive were downloaded from the CADC in 2006 May.
(Photometry and polarimetry data were ignored.) A full description of
the instrumental characteristics of SCUBA was made by Holland et al.
(1999MNRAS.303..659H 1999MNRAS.303..659H).
All maps are available at
http://www3.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/community/scubalegacy/
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 240 5061 The Fundamental Map Object Catalog (JCMTSF)
table3.dat 240 6118 The Extended Map Object Catalog (JCMTSE)
sf850emi/* . 1423 Emission maps FITS files for fundamental catalog
se850emi/* . 1547 Emission maps FITS files for extended catalog
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See also:
J/MNRAS/358/149 : HDFN SCUBA Super-map. III (Pope+, 2005)
J/MNRAS/372/1621 : SCUBA Half-Degree Extragalactic Survey. II (Coppin+, 2006)
J/ApJ/653/383 : SCUBA observations in Orion A South region (Johnstone+ 2006)
J/ApJ/639/259 : Sub-mm clumps in Orion B South mol. cloud (Johnstone+, 2006)
http://www3.cadc-ccda.hia-iha.nrc-cnrc.gc.ca/community/scubalegacy : MAPS
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- --- [JCMTS]
6 A1 --- n [EF] (F for Table 2 or E for Table 3)
8- 23 A16 --- JCMTS Object identifier (JHHMMSS.s+DDMMSS) (1)
25- 32 F8.4 deg GLON Galactic longitude (2)
34- 41 F8.4 deg GLAT Galactic latitude (2)
43- 76 A34 --- MapFile FITS file containing the 850 micron map,
in "sf850emi" subdirectory (3)
78- 84 F7.2 Jy P850 Maximum 850um intensity in Jy/beam
86- 91 F6.1 arcsec R850 850um effective radius (4)
93- 98 F6.2 Jy rms850 Median 850um noise of object pixels in Jy/beam
100-106 F7.1 --- S/N850 850um signal-to-noise ratio
108-114 F7.2 Jy F850 850um flux (5)
116-123 F8.2 Jy A850 ?=-99.99 Alternative 850um flux (6)
125-129 F5.1 arcsec nR850 ?=-99.9 Effective radius of alternative area
131 A1 --- f_850 [c] Flag on the 850um data (7)
133-138 F6.3 --- Min850 Minimum 850um noise value in Map
140-145 F6.3 --- Med850 Median 850um noise value in Map
147-154 F8.3 Jy rms450 ?=-99.99 Median 450um noise of object
pixels in Jy/beam
156 A1 --- l_P450 Limit flag on P450
157-164 F8.2 Jy P450 ?=-99.99 Maximum 450um intensity in Jy/beam
166 A1 --- l_F450 Limit flag on F450
167-174 F8.2 Jy F450 ?=-99.99 450 micron flux
176 A1 --- l_P450/850 Limit flag on P450/850
177-184 F8.2 --- P450/850 ?=-99.99 Ratio of maximum 450 to 850 micron
intensities (7)
186 A1 --- l_F450/850 Limit flag on F450/850
187-193 F7.2 --- F450/850 ?=-99.99 Ratio of 450 to 850 micron fluxes (8)
195 A1 --- f_JCMTS [cMn] Flag on the 450/850 micron data (7)
197-201 A5 --- Edge Object proximity to edge of mapped area (9)
204-240 A37 --- ObjID Potential catalogued object identification
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Note (1): Based on the position of its pixel of maximum brightness
at 850 microns in J2000 coordinates. The convention used is
JCMTSn_JHHMMSS.S±DDMMSS where "JCMTS" is short for JCMT/SCUBA
and "n" is either "F" or "E" depending on whether the object is
in the Fundamental or Extended Catalogs respectively.
Note (2): To convert from J2000 to galactic coordinates, the J2000 position
of the North Galactic Pole was assumed to be (12:51:26.28+27:07:41.7)
and the galactic longitude of the ascending note of the Galactic
Equator was assumed to be 32.93192 degrees, following the ICRS system
values of these provided in the Hipparcos Catalogue (1997).
Note (3): All 1423 square-degree maps are also in sf850emi.tar file,
named Fundamental/850um/Emission_Maps/FileName
Note (4): Determined from the square root of the area of the object found
by Clumpfind divided by π. (Note that this is not the FWHM of a
given object.)
Note (5): Derived as the flux of the object over its area defined by
Clumpfind (i.e., down to a level equal to 3X the minimum noise of the
map of origin). To determine 850 micron fluxes, a Gaussian beam of
22.9arcsec FWHM was assumed (see Section 4).
Note (6): Derived as the flux within an alternative area, i.e. that defined
by a contour of 3X30mJy/beam = 90mJy/beam for all possible objects.
Determining fluxes for all objects within a common intensity threshold
allows fluxes between objects to be compared more easily. The common
threshold of 30mJy/beam was chosen to be representative of typical
noise levels of the 850micron maps, as seen in Figure 8.
Note (7): Flags as follows:
c = the maximum 850 micron intensity is not ≥5X30mJy/beam = 150mJy/beam.
M = no 450 micron data are present in the Fundamental Map Dataset at the
location of the 850 micron object.
n = median 450 micron noise of object exceeds 999Jy/beam.
Note (8): For these ratios, the maps at 850 micron and 450 micron were
convolved with beams from the other respective wavelength, to produce
maps at each wavelength with a common beam size. (After this
convolution, both maps are at the same resolution and have common
"error beams").
Note (9): Object proximity is:
clear = object was defined without any pixel extending to an area of the
sky not mapped by SCUBA.
edge = object extends to a map edge, and the determined fluxes should be
considered as lower limits.
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History:
* 17-Jun-2009: From electronic version of the journal
* 19-Oct-2010: FITS files of extended catalog (se850emi subdirectory)
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 17-Jun-2009