Dark energy and dark matter haloes

We investigate the effect of dark energy on the density profiles of dark matter haloes with a suite of cosmological N-body simulations and use our results to test analytic models. We consider constant equation of state models, and allow both w -1 and w -1 quintessence models seem to exacerbate the central density problem relative to the standard w = -1 model. For example, models with w -0.5 seem disfavoured by the data, which can be matched only by allowing extremely low normalizations, 8 0.6. Meanwhile w < -1 models help to reduce the apparent discrepancy. We confirm that the halo mass function of Jenkins et al. provides an excellent approximation to the abundance of haloes in our simulations and extend its region of validity to include models with w < -1.