Nonlinear Biasing and Redshift-Space Distortions in Lagrangian
  Resummation Theory and N-body Simulations
  Understanding a behavior of galaxy biasing is crucial for future galaxy
redshift surveys. One aim is to measure the baryon acoustic oscillations (BAOs)
within the precision of a few percent level. Using 30 large cosmological N-body
simulations for a standard LCDM cosmology, we study the halo biasing over a
wide redshift range. We compare the simulation results with theoretical
predictions proposed by Matsubara (2008) which naturally incorporate the halo
bias and redshift-space distortions into their formalism of perturbation theory
with a resummation technique via the Lagrangian picture. The power spectrum and
correlation function of halos obtained from Lagrangian resummation theory (LRT)
well agree with N-body simulation results on scales of BAOs. Especially
nonlinear effects on the baryon acoustic peak of the halo correlation function
are accurately explained both in real and redshift space. We find that
nonlinearity and scale dependence of bias are fairly well reproduced by 1-loop
LRT up to k=0.35hMpc^{-1} (z=2 and 3) within a few percent level in real space
and up to k=0.1hMpc^{-1} (z=2) and 0.15hMpc^{-1} (z=3) in redshift space. Thus,
the LRT is very powerful for accurately extracting cosmological information in
upcoming high redshift BAO surveys.
