A multifrequency method based on the Matched Multifilter for the detection of point sources in CMB maps

TL;DR

This paper introduces a multifrequency detection method using the Matched Multifilter technique to improve the identification of extragalactic point sources in CMB maps, outperforming traditional monofrequency filters.

Contribution

The paper presents a novel multifrequency filtering approach that leverages spatial and spectral information to enhance point source detection in CMB data.

Findings

Multifrequency method outperforms monofrequency matched filter in detection accuracy.

Improved completeness and reliability in point source detection.

Better flux and spectral index estimation with the new method.

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 apply a linear filtering technique that uses spatial information and the cross-power spectrum. To make this, we simulate realistic and non-realistic flat patches of the sky at two frequencies of Planck: 44 and 100 GHz. We filter to detect and estimate the point sources and compare this technique with the monofrequency matched filter in terms of completeness, reliability, flux and spectral index accuracy. The multifrequency method outperforms the matched filter at the two frequencies and in all the studied cases in the work.