The C-Band All-Sky Survey (C-BASS): Total intensity point-source
  detection over the northern sky
  We present a point-source detection algorithm that employs the second order
Spherical Mexican Hat wavelet filter (SMHW2), and use it on C-BASS northern
intensity data to produce a catalogue of point-sources. This catalogue allows
us to cross-check the C-BASS flux-density scale against existing source
surveys, and provides the basis for a source mask which will be used in
subsequent C-BASS and cosmic microwave background (CMB) analyses. The SMHW2
allows us to filter the entire sky at once, avoiding complications from edge
effects arising when filtering small sky patches. The algorithm is validated
against a set of Monte Carlo simulations, consisting of diffuse emission,
instrumental noise, and various point-source populations. The simulated source
populations are successfully recovered. The SMHW2 detection algorithm is used
to produce a $4.76\,\mathrm{GHz}$ northern sky source catalogue in total
intensity, containing 1784 sources and covering declinations
$\delta\geq-10^{\circ}$. The C-BASS catalogue is matched with the Green Bank
6\,cm (GB6) and Parkes-MIT-NRAO (PMN) catalogues over their areas of common sky
coverage. From this we estimate the $90$ per cent completeness level to be
approximately $610\,\mathrm{mJy}$, with a corresponding reliability of $98$ per
cent, when masking the brightest $30$ per cent of the diffuse emission in the
C-BASS northern sky map. We find the C-BASS and GB6 flux-density scales to be
consistent with one another to within approximately $4$ per cent.
