Adrien Kuntz (CFHT)

Title : Cross-correlating CFHTLenS Galaxy Catalogue and Planck CMB Lensing

Abstract : In the framework of the standard cosmological model,
galaxies form in matter overdensities that are the result of the
growth of primordial inhomogeneities generated by inflation. As a
photon travels from its surface of last scattering to us, its path is
deflected by the large-scale structures of the universe. Using weak
gravitational lensing of the Cosmic Microwave Background (CMB),
characterized by temperature and polarization anisotropies, allows us
to reconstruct a map of the integrated (over the line of sight)
density of matter of the universe.  During my internship, I have
cross-correlated the CFHTLenS galaxy catalogue and the weak
gravitational lensing convergence map from the Planck team for the
2013 and 2015 releases. From this correlation I have derived a galaxy
bias and I have partially confirmed the surprising result of Omori and
Holder (2015) who found a difference between the 2013 and the 2015
releases of Planck.  After a reminder on cosmology, this presentation
will first focus on the theoretical part of my work on the halo model,
then present the results I obtained from the data and their
implication.