Cosmological Simulations of Number Counts

Understand

In this paper we present for the first time the angular power spectra $C_\ell(z,z')$ for number counts from relativistic N-body simulations.

• We use the relativistic N-body code gevolution with its exact integration of lightlike geodesics which include all relativistic scalar contributions to the number counts.
• We compare our non-perturbative numerical results with the results from CLASS using the HMCODE approximation for the non-linear matter power spectrum.
• We find that this simple description is excellent for both, the density and the convergence.