The very bright SCUBA galaxy count: looking for SCUBA galaxies with the   Mexican Hat Wavelet
  We present the results of a search for bright high-redshift galaxies in two large SCUBA scan-maps of Galactic regions. A Mexican Hat Wavelet technique was used to locate point sources in these maps, which suffer high foreground contamination as well as typical scan-map noise signatures. A catalogue of point source objects was selected and observed again in the submillimetre continuum, and in HCO+ (3->2) at zero redshift to rule out Galactic sources. No extragalactic sources were found. Simulations show that the survey was sensitive to sources with fluxes > 50 mJy, depending on the local background. These simulations result in upper limits on the 850-micron counts of SCUBA galaxies of 53 per square degree at 50 mJy and 2.9 per square degree at 100 mJy. 
V. E. Barnard, P. Vielva, D. P. I. Pierce-Price, A. W. Blain, R. B.   Barreiro, J. S. Richer and C. Qualtrough