J/MNRAS/423/529 AzTEC deep-field observations (Downes+, 2012)
Calculating the transfer function of noise removal by principal component
analysis and application to AzTEC deep-field observations.
Downes T.P., Welch D., Scott K.S., Austermann J., Wilson G.W., Yun M.S.
<Mon. Not. R. Astron. Soc., 423, 529-542 (2012)>
=2012MNRAS.423..529D 2012MNRAS.423..529D
ADC_Keywords: Surveys; Galaxies, radio; Millimetric/submm sources
Keywords: atmospheric effects - methods: data analysis -
galaxies: high-redshift - galaxies: starburst -
submillimetre: galaxies
Abstract:
Instruments using arrays of many bolometers have become increasingly
common in the past decade. The maps produced by such instruments
typically include the filtering effects of the instrument as well as
those from subsequent steps performed in the reduction of the data.
Therefore interpretation of the maps is dependent upon accurately
calculating the transfer function of the chosen reduction technique on
the signal of interest. Many of these instruments use non-linear and
iterative techniques to reduce their data because such methods can
offer an improved signal-to-noise ratio over those that are purely
linear, particularly for signals at scales comparable to that
subtended by the array. We discuss a general approach for measuring
the transfer function of principal component analysis on point sources
that are small compared to the spatial extent seen by any single
bolometer within the array. The results are applied to previously
released AzTEC catalogues of the Cosmic Evolution Survey (COSMOS),
Lockman Hole, Subaru XMM-Newton Deep Field, Great Observatories
Origins Deep Survey (GOODS)-North and GOODS-South fields. Source flux
density and noise estimates increase by roughly +10 per cent for
fields observed while AzTEC was installed at the Atacama Submillimeter
Telescope Experiment and +15-25 per cent while AzTEC was installed at
the James Clerk Maxwell Telescope. Detection significance is, on
average, unaffected by the revised technique. The revised photometry
technique will be used in subsequent AzTEC releases.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 50 The AzTEC point-source catalogue for the
COSMOS field as observed from the JCMT
table2.dat 88 40 The AzTEC point-source catalogue for the
GOODS-North field
table3.dat 88 95 The AzTEC point-source catalogue for the
Lockman Hole field
table4.dat 88 65 The AzTEC point-source catalogue for the
Subaru XMM-Newton Deep Field
table5.dat 88 57 The AzTEC point-source catalogue for the
GOODS-South field
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See also:
J/MNRAS/385/2225 : AzTEC millimetre survey of COSMOS field (Scott+, 2008)
J/MNRAS/401/160 : AzTEC survey of the SHADES fields. I. (Austermann+, 2010)
J/MNRAS/405/2260 : GOODS-S field AzTEC/ASTE Deep 1.1mm imaging (Scott+, 2010)
J/MNRAS/411/102 : AzTEC/ASTE 1.1mm observations in the ADF-S (Hatsukade+ 2011)
J/MNRAS/415/3831 : AzTEC/ASTE source catalogue (Aretxaga+, 2011)
Byte-by-byte Description of file: table?.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- --- [AzTEC_]
7- 25 A19 --- AzTEC AzTEC name (JHHMMSS.ss+DDMMSS.s)
27- 41 A15 --- Name Other name (4)
42 A1 --- n_Name [abc] Source not in both versions (1)
44- 47 F4.1 --- S/N Signal-to-noise ratio of the detection
49- 52 F4.1 mJy S1.1 Measured flux density at 1.1mm
54- 56 F3.1 mJy e_S1.1 rms uncertainty on S1.1
58- 61 F4.1 mJy S1.1c ?=- Corrected flux density at 1.1mm (2)
63- 65 F3.1 mJy E_S1.1c ? Error on S1.1c (upper value, 68%) (2)
67- 69 F3.1 mJy e_S1.1c ? Error on S1.1c (lower value, 68%) (2)
71- 74 F4.2 --- Pneg ?=- Probability that the source will deboost
to S<0 assuming the number counts prior
based on all AzTEC measurements, P(<0)
76- 79 F4.1 % dFlux ?=- Relative increase in Flux (3)
81- 84 F4.1 % dNoise ?=- Relative increase in noise (3)
86- 88 F3.1 arcsec theta ?=- Change in location of the source centroid
position if it was detected in both catalogues
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Note (1): Notes as follows:
a = indicates a source passed a significance test in the original catalogue,
but not the same test in the new catalogue. In each case, an estimate
for the missing quantity is made from the nearest pixel in the map in
which the test did not succeed.
b = indicates a source passed a significance test in the new catalogue, but
not the same test in the original catalogue. In each case, an estimate
for the missing quantity is made from the nearest pixel in the map in
which the test did not succeed.
c = a source found in the extended, lower coverage regions of the map
Note (2): flux density and 68 per cent confidence interval of the deboosted flux
density, including corrections for the bias to peak locations in the map.
Note (3): relative increase in flux and noise estimate for each source
if it was detected in the previously released catalogue.
Note (4): names in the tables:
1 = AzTEC/COSMOS NN (COSMOS field)
2 = AzTEC/GN NN (GOODS North field )
3 = AzTEC/LH NN (Lockman Hole field)
4 = AzTEC/SXDF NN (Subaru XMM-Newton Deeo Field)
5 = AzTEC/GS NN (GOODS South field)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Feb-2013