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arXiv · 1103.1166

Foreground component separation with generalised ILC

Mathieu Remazeilles·Jacques Delabrouille·Jean-Francois Cardoso
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Abstract

The 'Internal Linear Combination' (ILC) component separation method has been extensively used to extract a single component, the CMB, from the WMAP multifrequency data. We generalise the ILC approach for separating other millimetre astrophysical emissions. We construct in particular a multidimensional ILC filter, which can be used, for instance, to estimate the diffuse emission of a complex component originating from multiple correlated emissions, such as the total emission of the Galactic interstellar medium. The performance of such generalised ILC methods, implemented on a needlet frame, is tested on simulations of Planck mission observations, for which we successfully reconstruct a low noise estimate of emission from astrophysical foregrounds with vanishing CMB and SZ contamination.

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Mathieu Remazeilles, Jacques Delabrouille, Jean-Francois Cardoso. 2011-08-30. Foreground component separation with generalised ILC. https://doi.org/10.1111/j.1365-2966.2011.19497.x

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