kSZ velocity reconstruction and N-body Simulation
Utkarsh Giri and Kendrick Smith
Perimeter Institute of Theoretical Physics
kinetic Sunyaev Zeldovich (kSZ) effect is a secondary anisotropy in the CMB temperature caused by the scattering of CMB photons by ionized structures moving with some bulk velocity. By combining CMB maps with a galaxy survey, one can reconstruct the large scale velocity modes of the universe with better noise properties than the survey itself. In this presentation, I talk about a quadratic estimator that achieves this reconstruction and explore its properties using N-body simulation. I also talk about how one can use the reconstructed velocity field to improve constraints on primordial non-gaussianity parameter fnl.