CMB at small scales: Cosmology from tSZ power spectrum
  Small scale CMB angular power spectrum contains not only primordial CMB
information but also many contaminants coming from secondary anisotropies. Most
of the latter depend on the cosmological model but are often marginalised over.
We propose a new analysis of the SPT data focusing on the cosmological
contribution of the thermal Sunyaev Zel'dovich (tSZ) effect. We model the tSZ
angular spectrum with the halo model and train a random forest algorithm to
speed up its computation. We show that using the cosmological information of
the tSZ on top of the primordial CMB one contained in SPT data bring more
constraints on cosmological parameters. We also combine for the first time
Planck tSZ angular power spectrum with SPT ones to put further constraints.
This proof of concept study shows how much a proper modelling of the
foregrounds in the cosmological analyses is needed.
