SUMSS - Sydney University Molonglo Sky Survey (SUMSS) Source Catalog

Overview

The Sydney University Molonglo Sky Survey (SUMSS) is a radio imaging survey of the sky south of declination, delta = -30 degrees (a total area of 8100 square degrees) carried out with the Molonglo Observatory Synthesis Telescope (MOST) operating at 843 MHz. The survey consists of 629 4.3 degrees by 4.3 degrees mosaic images with a resolution of 45" by 45" x cosec delta, and a limiting peak brightness of 6 mJy/beam at declinations delta <= 50 degrees, and 10 mJy/beam at delta > 50 degrees. The SUMSS is therefore similar in sensitivity and resolution to the northern NRAO VLA Sky Survey (NVSS). This table based on the latest version of the SUMSS Source Catalog of radio sources (which uses all of the released mosaics).

Sources were found by fitting two-dimensional Gaussians to SUMSS mosaics. Positions in the catalog are accurate to within 1-2" for sources with peak brightness >= 20 mJy/beam, and are always better than 10". The internal flux density scale is accurate to within 3%. Image artifacts were classified using a decision tree, which correctly identified and rejected spurious sources in over 96% of cases. Analysis of the catalog shows that it is highly uniform and is complete to 8 mJy at delta <= -50 degrees, and to 18 mJy at delta > -50 degrees.

Catalog Bibcode

2003MNRAS.342.1117M

Bulletin

The SUMSS database table was last updated on 16 February 2012.

References

SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky.
   I. Science Goals, Survey Design, and Instrumentation

   Bock, D. C.-J., Large, M. I., Sadler, E. M.
   1999, AJ, Volume 117, p. 1578
   (1999AJ....117.1578B)

SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky.
  II. The Source Catalogue

   Mauch, T., Murphy, T., Buttery, H. J., Curran, J., Hunstead, R. W.,
   Piestrzynski, B., Robertson, J. G., Sadler, E. M.
   2003, MNRAS, Volume 342, p. 1117
   (2003MNRAS.342.1117M)

The Molonglo Galactic Plane Survey (MGPS-2): Compact Source Catalogue

   Murphy, T., Mauch, T., Green, A., Hunstead, R. W., Piestrzynski, B.,
   Kels, A.P., Sztajer, P.
   2007, MNRAS, in press

Provenance

This HEASARC table was initially created in August 2005. It is updated automatically within a week of any detected change to the SUMSS Source Catalog as obtained from the SUMSS Website at the following URL:

         http://www.astrop.physics.usyd.edu.au/sumsscat/update

Parameters

Name
The SUMSS source designation, created by the HEASARC from the J2000 coordinates using the IAU-recommended position-based method and the prefix "SUMSS" and according to the prescription given in SUMSS II.

RA
The Right Ascension of the source in the selected equinox. This was given in J2000 coordinates to a precision of 0.01 seconds of time in the original table.

Dec
The Declination of the source in the selected equinox. This was given in J2000 coordinates to a precision of 0.1 arcseconds in the original table.

LII
The Galactic Longitude of the source.

BII
The Galactic Latitude of the source.

RA_Error
The uncertainty in the Right Ascension of the source, in arcseconds, calculated from the quadratic sum of the MOST Right Ascension calibration uncertainty (1.5") and equation 2 of the catalog paper (SUMSS II: Mauch et al. 2003).

Dec_Error
The uncertainty in the Declination of the source, in arcseconds, calculated from the quadratic sum of the MOST Declination calibration uncertainty (1.7") and equation 3 of the catalog paper (SUMSS II: Mauch et al. 2003).

Flux_36_cm
The 843 MHz (36 cm) peak brightness of the source, in units of mJy/beam. Two of the sources in this catalog, SUMSS J132528-430110 (Cen A) and SUMSS J132110-434249 (NGC 5090), have been assigned peak brightnesses of 0.0 mJy/beam. The entries for these sources were added to the catalog by hand (by the authors) as they were too complex for an elliptical Gaussian fit, and hence peak brightnesses were considered to be meaningless in these cases. Please refer to Section 6.3 of SUMSS Paper II for a description of how these two sources were included.

Flux_36_cm_Error
The associated uncertainty in the 843 MHz (36 cm) peak brightness calculated from the quadratic sum of equation 8 of the catalog paper (SUMSS II: Mauch et al. 2003) and the MOST flux density calibration uncertainty of 3 per cent, in units of mJy/beam.

Int_Flux_36_cm
The total (integrated) 36-cm flux density of the source, in mJy.

Int_Flux_36_cm_Error
The associated uncertainty in the total 36-cm flux density, calculated from the equations described in Condon (1997, PASP, 109, 166), in mJy.

Fit_Major_Axis
The fitted major axis of the source, in arcseconds.

Fit_Minor_Axis
The fitted minor axis of the source, in arcseconds.

Fit_Position_Angle
The fitted major axis position angle of the source, in degrees east of north. Most unresolved sources would have PA values close to 0 or 180 degrees, since the MOST elliptical beam has a position angle PA=0.

Major_Axis
The major axis of the source after deconvolution from the MOST beam, in arcseconds. This parameter is given if the fitted major axis size exceeds the beam size by more than 2.33 times the sigma of the fitted major axis size.

Minor_Axis
The minor axis of the source after deconvolution from the MOST beam, in arcseconds. If the major axis is resolved, the minor axis is subsequently checked using the same criterion, viz., this parameter is filled if the fitted minor axis size exceeds the beam size by more than 2.33 times the sigma of the fitted minor axis size.

Position_Angle
The deconvolved position angle of the source, in degrees east from north. This parameter is given if the major axis is resolved.

Mosaic_Name
The name of the mosaic in which the source appears. The original mosaics are available online at http://www.astrop.physics.usyd.edu.au/mosaics In the case of duplicate matches, the mosaic name quoted is that used for the fit which is chosen to be included in the catalog.

Number_Mosaics
The number of mosaics in which the source appears. This is included to let the user know when the source appears in more than one image. The source parameters which appear in the catalog are those for the most reliable fit.

X_Pixel
The X pixel position of the source on the quoted mosaic.

Y_Pixel
The Y pixel position of the source on the quoted mosaic.

Contact Person

Questions regarding the SUMSS database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:35:21 EDT