Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations

Details Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations

2011-01-07

arxiv.org/abs/1101.1520v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

17 pages, 16 figures. Matches version accepted by MNRAS

Scientific paper

10.1111/j.1365-2966.2011.18768.x

We test third-order standard perturbation theory (SPT) as an approximation to non-linear cosmological structure formation. A novel approach is used to numerically calculate the three-dimensional dark matter density field using SPT from the initial conditions of two high-resolution cosmological simulations. The calculated density field is compared to the non-linear dark matter field of the simulations both point-by-point and statistically. For smoothing scales above 8 Mpc/h it shows a good agreement up to redshift 0. We present a simple fitting formula to relate the linear and non-linear density contrast that accurately recovers the non-linear time evolution for 0 <= z <= 10 at the per cent level. To address the problem of biasing between the matter field and the haloes identified in the simulation, we employ the Eulerian local bias model (ELB), including non-linear bias up to the third order. The bias parameters are obtained by fitting a scatter plot of halo and matter density (both from the simulation and from SPT). Using these bias parameters, we can reconstruct the halo density field. We find that this reconstruction is not able to capture all the details of the halo distribution. We investigate how well the large scale bias can be described by a constant and if it corresponds to the linear bias parameter b_1 of the local bias model. We also discuss how well the halo-halo power spectrum and the halo-mass cross spectrum from the reconstructed halo density field agree with the corresponding statistics from the simulation. The results show that while SPT is an excellent approximation for the matter field for suitably large smoothing scales even at redshift 0, the ELB model can only account for some of the properties of the halo density field.

Affiliated with

Also associated with

No associations

Rating

Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Testing standard perturbation theory and the Eulerian local biasing scheme against N-body simulations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-7938