Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics
Scientific paper
2012-04-25
Astronomy and Astrophysics
Astrophysics
Cosmology and Extragalactic Astrophysics
21 pages, 12 figures
Scientific paper
We develop a new test of local bias, by constructing a locally biased halo density field from sampling the dark matter-halo distribution. Our test differs from conventional tests in that it preserves the full scatter in the bias relation and it does not rely on perturbation theory. We put forward that bias parameters obtained using a smoothing scale R can only be applied to computing the halo power spectrum at scales k ~ 1/R. Our calculations can automatically include the running of bias parameters and give vanishingly small loop corrections at low-k. Our proposal results in much better agreement of the sampling and perturbation theory results with the original simulations. In particular, unlike the standard interpretation of local bias in the literature, our treatment of local bias does not generate a constant power at very large scales, in agreement with our measurements in the simulations of the halo power spectrum at wavenumbers below its turn-over. Using perturbation theory and our non-perturbative sampling technique we also demonstrate that nonlocal bias effects discovered recently in simulations impact the power spectrum only at the few percent level in the weakly nonlinear regime.
Chan Kwan Chuen
Scoccimarro Roman
No associations
LandOfFree
Halo Sampling, Local Bias and Loop Corrections 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 Halo Sampling, Local Bias and Loop Corrections, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Halo Sampling, Local Bias and Loop Corrections will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-313058