A multifrequency method based on the matched multifilter for the detection of point sources in CMB maps

Abstract

In this work, we deal with the problem of simultaneous multifrequency detection of extragalactic point sources in maps of the cosmic microwave background. We developed a linear filtering technique that takes into account the spatial and the cross-power spectrum information at the same time. By using realistic simulations, we compared this technique with the monofrequency matched filter in terms of completeness, reliability, flux and spectral index accuracy. The multifrequency method outperforms the matched filter in all the studied cases in this work.