Low-l CMB Analysis and Inpainting

Understand

Reconstruction of the CMB in the Galactic plane is extremely difficult due to the dominant foreground emissions such as Dust, Free-Free or Synchrotron.

• For cosmological studies, the standard approach consists in masking this area where the reconstruction is not good enough.
• This leads to difficulties for the statistical analysis of the CMB map, especially at very large scales (to study for e.g., the low quadrupole, ISW, axis of evil, etc).
• We investigate in this paper how well some inpainting techniques can recover the low-$\ell$ spherical harmonic coefficients.