J/MNRAS/546/F1849 SMGPS compact source catalogue (Mutale+, 2026)
The SARAO MeerKAT Galactic Plane Survey compact source catalogue.
Mutale M., Thompson M.A., Williams G.M., Rigby A.J., Hoare M.G.,
Urquhart J.S., Bietenholz M.F., Bordiu C., Camilo C., Cotton W.D.,
Goedhart S., Obonyo W.O., Riggi S., Yang A.Y.
<Mon. Not. R. Astron. Soc. 546, staf1849 (2026)>
=2026MNRAS.546f1849M 2026MNRAS.546f1849M (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Galactic plane ; Radio continuum
Keywords: techniques: interferometric - catalogues - surveys -
Galaxy: general - Galaxy: structure - radio continuum: ISM
Abstract:
We present a catalogue of compact sources detected in the SARAO
MeerKAT 1.3GHz Galactic Plane Survey (SMGPS). We extract 510599
compact sources, with areas less than five 8{arcsec} beams, from the
survey maps covering the regions 252°<l<358° and
2°<l<61° at |b|≤1.5°, which have an angular resolution of
8{arcsec} and a sensitivity of ∼10-30µJy/beam. In this paper, we
describe the source identification and characterisation methods,
present the quality assurance of the catalogue, explore the nature of
the catalogue sources, and present initial science highlights. We
limit our catalogue to sources with a signal-to-noise ratio ≥5, as
the catalogue is ∼90 per cent complete, and has a false positive rate
of less than 1 per cent at this threshold. The bulk of the catalogue
sources are previously unknown to the literature, with the majority of
unknown sources at sub-mJy levels. Initial science highlights from the
catalogue include the detection of 213 radio quiet WISE HII region
candidates, previously undetected in radio continuum studies. We show
images that compare the SMGPS compact sources to CORNISH ultracompact
HII regions, thus highlighting the sensitivity and unprecedented
uv-coverage of the SMGPS, and the potential synergy of the SMGPS with
other surveys.
Description:
Names, coordinates, observed parameters, and quality assurance flags
of 510599 compact radio sources (area<5 synthesized beams) detected
in the SMGPS above a signal-to-noise threshold of 5.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
smgpscsc.dat 525 510599 SMGPS compact source catalogue
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Byte-by-byte Description of file: smgpscsc.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- CSC Catalogue source identification number
(csc_id)
8- 23 A16 --- Name Galactic source name (GLLL.llll+B.bbbb)
(Name)
25- 48 A24 --- IAUName IAU designation of the source name
(SMGPS-CSC GLLL.llll+B.bbb) (IAUName)
50- 62 A13 --- tileName File identifier of mosaic from which the
source was extracted (tileName)
64- 68 I5 --- island A group of 1 or more Gaussians identified
as pixels with contiguous source emission
(island)
70- 71 I2 --- source A single Gaussian component (source)
73- 95 E23.16 mJy/beam background Background flux density (background)
97-118 F22.19 mJy/beam localrms rms noise around the immediate vicinity of
the source (local_rms)
120-139 F20.16 deg GLON Galactic longitude of the centroid
position of the source (lon)
141-162 E22.16 deg e_GLON ?=- Source-extraction fitting error on
Galactic longitude (err_lon)
164-186 E23.16 deg GLAT Galactic latitude of the centroid
position of the source (lat)
188-209 E22.16 deg e_GLAT ?=- Source-extraction fitting error on
Galactic latitude (err_lat)
211-217 F7.3 deg RAdeg Right Ascension of the centroid position
of the source (J2000) (ra)
219-231 F13.9 deg DEdeg Declination of the centroid position
of the source (J2000) (dec)
233-256 F24.18 mJy/beam Fpeak Peak flux density 1.3GHz (peak_flux)
258-285 F28.19 mJy/beam e_Fpeak ?=- Source-extraction fitting error on
peak flux density 1.3GHz (errpeakflux)
287-310 F24.18 mJy Fint Integrated flux density 1.3GHz (calculated
as a/b/peak_flux) (int_flux)
312-339 F28.19 mJy e_Fint ?=- Source-extraction fitting error on
integrated flux density 1.3GHz
(errintflux)
341-359 F19.16 arcsec amaj Fitted major axis (a)
361-382 E22.16 arcsec e_amaj ?=- Error on fitted major axis (err_a)
384-402 F19.16 arcsec bmin Fitted minor axis (b)
404-425 E22.16 arcsec e_bmin ?=- Error on fitted minor axis (err_b)
427-449 E23.15 deg PA [] Fitted position angle (pa)
451-472 E22.15 deg e_PA ?=- Error on fitted position angle
(err_pa)
474-475 I2 --- Flags Fitting flags (flags) (1)
477-498 F22.16 --- SNR Signal-to-noise ratio (calculated as
peakflux/localrms) (snr)
500-518 F19.15 arcsec2 Area Source area (calculated as pi.a.b/4ln2)
(ea)
520-525 A6 --- nbs Near bright source flag (nbs) (2)
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Note (1): Flags are defined as follows :
0 = good fit
1 = islands were not able to be fit due to there being fewer pixels than
free parameters
2 = an error occurred during the fitting process.
e.g. the fit didn't converge
4 = component was forced to have the shape of
the local point spread function
8 = source was forced to have a circular shape
16 = a component was not fit
32 = conversion from pixel to sky coordinates didn't work.
e.g. due to pixels in the image that don't have valid sky coordinates
or due to strange projections
Note (2): Flags defined as follows:
bright = source has flux density >0.5Jy
yes = source is within 0.5 degrees of a 0.5Jy bright source
no = source is not within 0.5 degrees of a 0.5Jy bright source
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Acknowledgements:
Mubela Mutale, m.mutale(at)leeds.ac.uk
(End) Patricia Vannier [CDS] 29-Oct-2025