Some like it triaxial: the universality of dark matter halo shapes and their evolution along the cosmic time

Understand

We present a detailed analysis of dark matter halo shapes, studying how the distributions of ellipticity, prolateness and axial ratios evolve as a function of time and mass.

• With this purpose in mind, we analysed the results of three cosmological simulations, running an ellipsoidal halo finder to measure triaxial halo shapes.
• The simulations have different scales, mass limits and cosmological parameters, which allows us to ensure a good resolution and statistics in a wide mass range, and to investigate the dependence of halo properties on the cosmological model.
• We confirm the tendency of haloes to be prolate at all times, even if they become more triaxial going to higher redshifts.