A European team, involving researchers from the l’Ecole Polytechnique Fédérale de Lausanne (EPFL) and the Astrophysical Department Sap-AIM of CEA-Irfu, has found that some of the defects in the Cosmic Microwave Background of the universe present in the images obtained by the WMAP and Planck satellites may only be due to poor image reconstruction and incomplete subtraction of the contributions of our own galaxy. These results are published in the Journal of Cosmology and Astroparticle Physics August 2014.
The LGMCA method has been used to reconstruct the Cosmic Microwave Background (CMB) image from WMAP 9 year and Planck-PR1 data. Based on the sparse modeling of signals – a framework recently developed in applied mathematics – the proposed component separation method is well-suited for the extraction of foreground emissions.
A joint WMAP9 year and Planck PR1 CMB has been reconstructed for the first time and produce a very high quality CMB map, especially on the galactic center where it is the most difficult due to the strong foreground emissions of our Galaxy. This webpage provides some comparisons between the PR1 and WPR1 maps and codes to recompute the map in the spirit of reproducible research.