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Table 3

Properties of the FIRST and NVSS radio continuum surveys.


effective resolution 5′′ 45′′
completeness limit 1 mJya  ~2.5 mJy
positional uncertaintyb  <0.5′′  <1′′
positional uncertaintyc  1′′  ~7′′
total number of sources 816 331d 1 810 6723
sources per square degree  ~90  ~53
area covered (deg2) 9055 33 885



Catalog detection threshold;


for the brightest sources;


at the completeness limit/detection threshold;


as of July 16, 2008;


as of February, 2004.

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