Biases on the cosmological parameters and thermal Sunyaev-Zel'dovich residuals

Abstract

Listen

Translate article

We examine the biases induced on cosmological parameters when the presence of secondary anisotropies is not taken into account in Cosmic Microwave Background analyses. We first develop an exact analytical expression for computing the biases on parameters when any additive signal is neglected in the analysis. We then apply i t in the context of the forthcoming Planck experiment. For illustration, we investigate the effect of the sole residual thermal Sunyaev‐Zel’dovich signal that remains after cluster extr action. We find in particular that analyses neglecting the presence of this contribution intr oduce on the cosmological parameters ns andτ biases, at least∼ 6.5 and 2.9 times their oneσ confidence intervals. The b parameter is also biased to a lesser extent.