The Effects of Varying Cosmological Parameters on Halo Substructure

Understand

We investigate how different cosmological parameters, such as those delivered by the WMAP and Planck missions, affect the nature and evolution of dark matter halo substructure.

• We use a series of flat $\Lambda$ cold dark matter ($\Lambda$CDM) cosmological $N$-body simulations of structure formation, each with a different power spectrum but the same initial white noise field.
• Our fiducial simulation is based on parameters from the WMAP 7th year cosmology.
• We then systematically vary the spectral index, $n_s$, matter density, $\Omega_M$, and normalization of the power spectrum, $\sigma_8$, for 7 unique simulations.