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MGPS2 - Molonglo Galactic Plane Survey 2nd Epoch Compact Source Catalog |
This table contains the Molonglo Galactic Plane Survey 2nd Epoch
(MGPS-2) Compact Source Catalog. The MGPS-2 was carried out with the Molonglo
Observatory Synthesis Telescope (MOST) at a frequency of 843 MHz and with a
restoring beam of 45" x 45" cosec |(delta)|, where delta is the declination,
making it the highest resolution large-scale radio survey of the southern
Galactic plane to date. It covers the range |b| < 10 degrees and
245 < l < 365 degrees, where l and b are the Galactic longitude and
latitude, and is the Galactic counterpart to the SUMSS (CDS Cat. VIII/81)
Catalog which covers that portion of the southern sky with delta < -30 degrees,
|b| > 10 degrees.
This version of the catalog (15-Aug-2007) consists of 48850 compact sources,
made by fitting elliptical gaussians in the MGPS-2 mosaics to a limiting
peak brightness of 10 mJy/beam. The authors used a custom method (described in
the associated reference publication) to remove extended sources from the
catalog. Positions in the catalog are accurate to 1" - 2". The authors have
carried out an analysis of the compact source density across the Galactic
plane and find that the source density is not statistically higher than the
density expected from the extragalactic source density alone.
See http://www.astrop.physics.usyd.edu.au/mosaics for access to the
MGPS-2 mosaic images.
2007MNRAS.382..382M
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, Volume 382, p. 382
(2007MNRAS.382..382M)
This HEASARC table was created in January 2008 based on CDS
catalog J/MNRAS/382/382 file mgpscat.dat.
Name
The MGPS-2 source designation (MGPS JHHMMSS-DDMMSS) provided by the
authors, using the IAU-recommended position-based method.
RA
The Right Ascension of the radio 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 radio 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 radio source.
BII
The Galactic Latitude of the radio source.
RA_Error
The uncertainty in the Right Ascension of the radio source, in
arcseconds, calculated from the quadratic sum of the MOST Right Ascension
calibration uncertainty and equation (1) of the reference paper.
Dec_Error
The uncertainty in the Declination of the radio source, in
arcseconds, calculated from the quadratic sum of the MOST Declination
calibration uncertainty and equation (2) of the reference paper.
Flux_36_cm
The 843 MHz (36 cm) peak brightness of the source, in units of
mJy/beam, calculated as described in Section 5.3 of the reference paper.
Flux_36_cm_Error
The 1-sigma uncertainty in the radio source peak brightness
at 843 MHz, in mJy/beam, calculated as described in Section 5.3 of the
reference paper.
Int_Flux_36_cm
The total flux density of the radio source at 843 MHz, in
mJy.
Int_Flux_36_cm_Error
The uncertainty in the total flux density of the
radio source at 843 MHz, in mJy, calculated from the equations described by
Condon (1997, PASP, 109, 166).
Fit_Major_Axis
The fitted size of the major axis of the radio source,
in arcseconds.
Fit_Minor_Axis
The fitted size of the minor axis of the radio source,
in arcseconds.
Fit_Position_Angle
The fitted major axis position angle of the radio 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 degrees.
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, and the deconvolved size is given.
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 radio source appears.
The naming scheme for MGPS-2 mosaics is JHHMMMDD indicating the J2000 RA and
Dec of the mosaic centre, e.g., J0712M32. The original mosaics are available
online at http://www.astrop.physics.usyd.edu.au/mosaics. In the case where a
radio source appears in two mosaics (due to overlap), the mosaic name quoted
is the one for which the fitted parameters are included in the catalog.
Number_Mosaics
The number of mosaics in which the source appears. Sometimes
a source can appear in multiple mosaics because of a small overlap region used
to ensure all sources are properly imaged and not truncated. The source
parameters which appear in the catalog are those for the most reliable fit.
X_Pixel
The x-pixel position of the radio source in the quoted mosaic.
Y_Pixel
The y-pixel position of the radio source in the quoted mosaic.
Questions regarding the MGPS2 database table can be addressed to the
HEASARC User Hotline.
If you have any problems, please consult the help
page or mail ledas-help@star.le.ac.uk
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