Impact of Scale Dependent Bias and Nonlinear Structure Growth on the ISW Effect: Angular Power Spectra

Understand

We investigate the impact of nonlinear evolution of the gravitational potentials in the LCDM model on the Integrated Sachs-Wolfe (ISW) contribution to the CMB temperature power spectrum, and on the cross-power spectrum of the CMB and a set of biased tracers of the mass.

• We use an ensemble of N-body simulations to directly follow the potentials and compare results to perturbation theory (PT).
• The predictions from PT match the results to high precision for k<0.2 h/Mpc.
• We compute the nonlinear corrections to the angular power spectrum and find them to be <10% of linear theory for l<100.