Estimating the impact of recombination uncertainties on the cosmological parameter constraints from cosmic microwave background experiments

Understand

[Abridged] We use our most recent training set for the RICO code to estimate the impact of recombination uncertainties on the posterior probability distributions which will be obtained from future CMB experiments, and in particular the Planck satellite.

• Using a MCMC analysis to sample the posterior distribution of the cosmological parameters, we find that Planck will have biases of -0.7, -0.3 and -0.4 sigmas for n_S, Omega_b h2 and log(As), respectively, in the minimal 6-parameter LCDM model, if the description of the recombination history given by RICO is not used.
• The remaining parameters are not significantly affected.
• We also show, that the cosmology dependence of the corrections to the recombination history modeled with RICO has a negligible impact on the posterior distributions obtained for the case of the Planck satellite.