Implications of bias evolution on measurements of the integrated Sachs-Wolfe effect: errors and biases in parameter estimation

Understand

The subject of this paper is a quantification of the impact of uncertainties in bias and bias evolution on the interpretation of measurements of the integrated Sachs-Wolfe effect, in particular on the estimation of cosmological parameters.

• We carry out a Fisher-matrix analysis for quantifying the degeneracies between the parameters of a dark energy cosmology and bias evolution, for the combination of the PLANCK microwave sky survey with the EUCLID main galaxy sample, where bias evolution b(a)=b_0+(1-a)b_a is modelled with two parameters b_0 and b_a.
• Using a realistic bias model introduces a characteristic suppression of the iSW-spectrum on large angular scales, due to the altered distance-weighting functions.
• The errors in estimating cosmological parameters if the data with evolving bias is interpreted in the framework of cosmologies with constant bias is quantified in an extended Fisher-formalism.