Séminaire Doctoral / Seminar PhD |
| « Annoying foregrounds in CMB and what we can do about it » |
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Caterina Umilta |
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The Planck mission provided whole sky maps in the microwave range, which
have opened a window on precision cosmic microwave background (CMB) science in cosmology. For this purpose, accuracy in the separation technique of foreground astrophysical emissions becomes crucial. A lot of effort has been done within the Planck Collaboration, however, the CMB maps they delivered still have a residual foreground contamination too high for cosmological exploitation. Among these residuals, the unresolved point sources background is one of the most perturbing, since this is a not well known emission ad since it is degenerate with the small scales of the CMB angular power spectrum. I will present our work to tackle this problem, which is based on putting some prior constraint on the analysis to address the point sources contamination. This constraint breaks the degeneracy and allows, through the blind component separation algorithm SMICA, to better characterize the foreground residual, which is a crucial step towards estimating cosmological parameters. |
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mercredi 11 janvier 2017 - 17:00 Salle Entresol Daniel Chalonge, Institut d'Astrophysique |
| Page web du séminaire / Seminar's webpage |