rms noise\
& & & & & /mJy\
10C – shallow & & Aug 2008 – June 2010 & 15.7 & 30 & 0.1\
10C – deep & & Aug 2008 – June 2010 & 15.7 & 30 & 0.05\
GMRT & & Jul 2004 – Oct 2006 & 0.610 & & 0.06\
WSRT & @2012rsri.confE..22G & Dec 2006 – Jun 2007 & 1.4 & & 0.011\
OM2008 & @2008AJ....136.1889O & Dec 2001 – Jan 2004 & 1.4 & 1.6 & 0.0027\
OMK2009 & @2009AJ....137.4846O & Feb 2006 – Jan 2007 & 0.324 & 6 & 0.07\
BI2006 & @2006MNRAS.371..963B & Jan 2001 – Mar 2002 & 1.4 & 1.3 & 0.0046\
FIRST & @1997ApJ...475..479W & 1997 – 2002 & 1.4 & 5 & 0.15\
NVSS & @1998AJ....115.1693C & 1997 & 1.4 & 45 & 0.45\

![image](alpha_samples-eps-converted-to.pdf){width="\columnwidth"} ![image](flux_15_samples-eps-converted-to.pdf){width="\columnwidth"}

As many of these lower frequency catalogues have higher resolutions than the 10C survey, they also provide more accurate positions which are vital when searching for multi-wavelength counterparts for the 10C. It is therefore useful to define a complete sub-sample of sources which have 1.4-GHz data available. For this purpose, we used the BI2006, OM2008 and WSRT surveys as they are the 