Dec 3 (Thu), 14:15 in A311
Halo clustering in Lagrangian space
Although we observe halos (or galaxies) in Eulerian space, modeling of halo clustering often starts with halos in the Lagrangian space. We construct Lagrangian halos by tracing the particles in Eulerian halos back to Lagrangian space in N-body simulations to study their properties. The window function for Lagrangian halos always appears in the theoretical modelling of the Lagrangian halos. Although the window is often assumed to be a top-hat, we find that it is more smooth than a top-hat, but less diffuse than a Gaussian. Using this effective window function together with the scale-dependent excursion set bias parameters we are able to fit the Lagrangian cross bias parameter in Fourier space well up to k R_{Lag} ~ 10, where R_{Lag} is the Lagrangian size of the halo. Furthermore we check the so-called Lagrangian bias consistency relations. These powerful relations not only enable us to check the self-consistency of the biasing prescription, it can also allow us to extract the halo formation physics.