J/MNRAS/476/2717 AT20G-MWACS catalogue (Harvey+, 2018)
A novel approach for characterizing broad-band radio spectral energy
distributions.
Harvey V.M., Franzen T., Morgan J., Seymour N.
<Mon. Not. R. Astron. Soc., 476, 2717-2730 (2018)>
=2018MNRAS.476.2717H 2018MNRAS.476.2717H (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; Galaxies, radio
Keywords: methods: analytical - techniques: photometric - catalogues -
radio continuum: galaxies
Abstract:
We present a new broad-band radio frequency catalogue across
0.12GHz≤ν≤20GHz created by combining data from the Murchison
Widefield Array Commissioning Survey, the Australia Telescope 20GHz
survey, and the literature. Our catalogue consists of 1285 sources
limited by S20GHz>40mJy at 5σ, and contains flux density
measurements (or estimates) and uncertainties at 0.074, 0.080, 0.119,
0.150, 0.180, 0.408, 0.843, 1.4, 4.8, 8.6, and 20GHz. We fit a
second-order polynomial in log-log space to the spectral energy
distributions of all these sources in order to characterize their
broad-band emission. For the 994 sources that are well described by a
linear or quadratic model we present a new diagnostic plot arranging
sources by the linear and curvature terms. We demonstrate the
advantages of such a plot over the traditional radio colour-colour
diagram. We also present astrophysical descriptions of the sources
found in each segment of this new parameter space and discuss the
utility of these plots in the upcoming era of large area, deep,
broad-band radio surveys.
Description:
We have created a new source catalogue, AT20G-MWACS, by building on
the solid high-frequency foundation of the AT20G survey and combining
it with the results of a fresh run of source finding algorithms on the
original MWACS images. The catalogue covers an area of 5760deg2 and
contains 1285 sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 746 1285 AT20G-MWACS catalogue
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See also:
VIII/98 : 180MHz Murchison Commissioning Survey (MWACS)
(Hurley-Walker+, 2014)
J/MNRAS/402/2403 : Australia Telescope 20GHz Survey Catalog, AT20G
(Murphy+, 2010)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- AT20G AT20G IAU designation (JHHMMSS+DDMMSS)
20- 40 F21.17 deg RAdeg AT20G right ascension (J2000)
42- 60 F19.15 deg DEdeg AT20G declination (J2000)
62- 67 F6.1 mJy/beam S20G ?=- AT20G Peak brightness at 20GHz
69- 88 F20.16 mJy/beam e_S20G ?=- Uncertainty on S20G with
an additional 10% of S20G added
in quadrature
90- 94 F5.1 mJy/beam e_S20G-orig AT20G Uncertainty on S20G
96-101 F6.1 mJy/beam S8G ?=- AT20G Peak brightness at 8.6GHz
103-122 F20.16 mJy/beam e_S8G ?=- Uncertainty on S8G with an additional
10% of S8G added in quadrature
124-128 F5.1 mJy/beam e_S8G-orig ?=- AT20G Uncertainty on S8G
130-135 F6.1 mJy/beam S5G ?=- AT20G Peak brightness at 4.8GHz
137-156 F20.16 mJy/beam e_S5G ?=- Uncertainty on S5G with an additional
10% of S5G added in quadrature
158-162 F5.1 mJy/beam e_S5G-orig ?=- AT20G Uncertainty on S5G
164-169 F6.1 mJy S1G ?=- AT20GHARC (NVSS) integrated (total)
1.4GHz flux density
171-190 F20.16 mJy e_S1G ?=- NVSS mean error on S1G
192-198 F7.1 mJy S843M ?=- AT20GHARC (SUMSS or MGPS-2)
integrated (total) 843MHz flux density
200-219 F20.16 mJy e_S843M ?=- SUMSS or MGPS-2 uncertainty on S843M
221-230 F10.4 mJy S408M ?=- MRC integrated flux density at 408MHz
232-242 F11.6 mJy e_S408M ?=- MRC error on S408MHz
244-264 F21.15 mJy S180M ?=0 MWACS-3If integrated (total) island
flux at 180.48MHz
(0.0 represents no detection)
266-286 F21.15 mJy e_S180M ?=0 MWACS-3If error on S180M (10% of flux
plus the local RMS added in quadrature)
288-308 F21.15 mJy S150M ?=0 MWACS-3If integrated (total) island
flux at 149.76MHz
(0.0 represents no detection)
310-329 F20.15 mJy e_S150M ?=0 MWACS-3If error on S150M (10% of flux
plus the local RMS added in quadrature)
331-350 F20.14 mJy S120M ?=0 MWACS-3If integrated (total) island
flux at 119.04MHz
(0.0 represents no detection)
352-371 F20.15 mJy e_S120M ?=0 MWACS-3If error on S120M (10% of flux
plus the local RMS added in quadrature)
373-379 F7.1 mJy S160M ?=- CCA integrated flux density at 160MHz
381-390 F10.5 mJy e_S160M ?=- CCA error on S160M
392-398 F7.1 mJy S80M ?=- CCA integrated flux density at 80MHz
400-405 F6.1 mJy e_S80M ?=- CCA error on S80M
407-417 F11.5 mJy S74M ?=- VLSS integrated flux density at 74MHz
419-429 F11.6 mJy e_S74M ?=- VLSS error on S74M
431-453 F23.17 mJy L180M MWACS-3If value of nearest pixel in
MWACS image
455-473 F19.15 mJy e_L180M MWACS-3If local RMS in MWACS image
475-497 F23.17 mJy L150M MWACS-3If value of nearest pixel in
MWACS image
499-517 F19.15 mJy e_L150M MWACS-3If local RMS in MWACS image
519-540 F22.16 mJy L120M MWACS-3If value of nearest pixel in
MWACS image
542-560 F19.15 mJy e_L120M MWACS-3If local RMS in MWACS image
562-566 F5.2 --- alpha1-20 ?=- AT20GHARC spectral index between
1 and 20GHz
568-572 F5.2 --- alpha5-8 ?=- AT20GHARC spectral index between
4.8 and 8.6GHz
574-578 F5.2 --- alpha8-20 ?=- AT20GHARC spectral index between
8.6 and 20GHz
580-587 E8.5 --- alpha0.18-1 ?=0 Spectral index between 180MHz and
∼1GHz
589-600 E12.5 GHz freqturn Frequency of the turning point of the
quadratic νturn
602-613 E12.5 GHz e_freqturn Uncertainty on the frequency of the
turning point of the quadratic
νturn
615-622 F8.5 GHz fluxRefFit ?=0 Reference flux of the best-fit model,
S0 (flux at 1GHz)
624-630 E7.5 GHz e_fluxRefFit ?=0 Uncertainty on the reference flux of
the best-fit model
632-639 E8.5 --- alphaFit ?=0 alpha of the best-fit model
641-647 F7.5 --- e_alphaFit ?=0 Uncertainty on alpha of the best-fit
model
649-656 F8.5 --- phiFit ?=0 phi of the best-fit model
658-664 F7.5 --- e_phiFit ?=0 Uncertainty on phi of the best-fit
model
666-675 F10.5 --- chiSqFit ?=0 Chi-squared of the best-fit model
677-686 F10.5 --- e_chiSqFit ?=0 Uncertainty on chi-squared of the
best-fit model
688-697 F10.5 --- rChiSqFit ?=- Reduced chi-squared of the best-fit
model
698 A1 --- n_rChiSqFit [I] I for +infinity
699-707 F9.5 --- e_rChiSqFit ?=- Uncertainty on reduced chi-squared
of the best-fit model
709-718 F10.5 --- AICcLin ?=0 AICc of the linear model
720-729 F10.5 --- AICcQuad ?=0 AICc of the quadratic model
731-734 F4.1 --- numData Number of measured data points available
to the fits
736-737 A2 --- fitClass Radio spectral class (RSC) flag
assigned to the source (1)
739-740 I2 --- fitClassInt [-4/4]? Integer representation of RSC (1)
742-744 A3 --- fitQual Fit quality flag assigned to the
source (2)
746 I1 --- fitQualInt [0/3]? Integer representation of fit
quality (2)
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Note (1): Integer representation of RSC as follows:
-4 = Ps, peaked, steep
-3 = Pf, peaked, flat
-2 = Pi, peaked, inverted
-1 = Ls, linear, steep
0 = Lf, linear, flat
+1 = Li, linear, inverted
+2 = Us, upturned, steep
+3 = Uf, upturned, flat
+4 = Ui, upturned, inverted
Note (2): Integer representation of fit quality as follows:
0 = g--, good
1 = px-, poor
2 = p-t, poor
3 = pxt, poor
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Apr-2021