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Using ENZO, a 3D adaptive mesh cosmological simulation code, we look at the characteristics of magnetic fields generated in early structure formation by the Biermann battery process. Tracking six species (H, H+, He, He+, He++ and e-), we follow the formation of structure from multiple independent realizations of cosmological initial conditions to better understand how magnetic fields are generated by non aligned pressure and density gradients. These efforts aim at adding ideal MHD to the ENZO framework which will enable the study of the build up and evolution of cosmic magnetic fields. [ABSTRACT FROM AUTHOR]

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble those formed by hierarchical clustering from realistic initial conditions in a CDM universe and, therefore, serve as a test-bed model for studying halo dynamics. The dark matter density profile is close to the universal halo profile identified previously from N-body simulations of structure formation in CDM, with a total mass and concentration parameter which grow linearly with scale factor a. When gas is included, this concentration parameter is slightly larger than the pure N-body result. We also find that the dark matter velocity distribution is less isotropic and more radial than found by N-body simulations of CDM. [ABSTRACT FROM AUTHOR]