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 .
We find that the best-fit values of all parameters are shifted by an amount comparable to the statistical accuracy : The estimation bias in units of the statistical accuracy amounts to 1.19 for \Omega _ { m } , 0.27 for \sigma _ { 8 } , and 0.72 for w for bias evolution with b _ { a } = 1 .
Leaving b _ { a } open as a free parameter deteriorates the statistical accuracy , in particular on \Omega _ { m } and w .