Modelling baryon acoustic oscillations with perturbation theory and stochastic halo biasing

DOI: 
10.1093/mnrasl/slt172
Publication date: 
01/03/2014
Main author: 
Kitaura F.-S.
IAA authors: 
Prada F.
Authors: 
Kitaura F.-S., Yepes G., Prada F.
Journal: 
Monthly Notices of the Royal Astronomical Society: Letters
Publication type: 
Article
Volume: 
439
Pages: 
L21-L25
Number: 
slt172
Abstract: 
In thiswork we investigate the generation ofmock halo catalogues based on perturbation theory and non-linear stochastic biasing with the novel PATCHY code. In particular, we use Augmented Lagrangian Perturbation Theory (ALPT) to generate a dark matter density field on a mesh starting from Gaussian fluctuations and to compute the peculiar velocity field. ALPT is based on a combination of second order LPT (2LPT) on large scales and the spherical collapse model on smaller scales. We account for the systematic deviation of perturbative approaches from N-body simulations together with halo biasing adopting an exponential bias model. We then account for stochastic biasing by defining three regimes: a low-, an intermediate- and a high-density regime, using a Poisson distribution in the intermediate regime and the negative binomial distribution - including an additional parameter - to model over-dispersion in the high-density regime. Since we focus in this study on massive haloes,we suppress the generation of haloes in the low-density regime. The various non-linear and stochastic biasing parameters, and density thresholds, are calibrated with the large BigMultiDark N-body simulation tomatch the power spectrum of the corresponding halo population. Our model effectively includes only five parameters, as they are additionally constrained by the halo number density. Our mock catalogues show power spectra, in both real- and redshift-space, which are compatible with N-body simulations within about 2 per cent up to k ~ 1 h Mpc-1 at z = 0.577 for a sample of haloes with the typical Baryon Oscillation Spectroscopic Survey (BOSS) CMASS (constant stellar mass galaxy sample) galaxy number density. The corresponding correlation functions are compatible down to a fewMpc.We also find that neglecting over-dispersion in high-density regions produces power spectra with deviations of 10 per cent at k~0.4 h Mpc-1. These results indicate the need to account for an accurate statistical description of the galaxy clustering for precise studies of large-scale surveys. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
Database: 
WOK
SCOPUS
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2014MNRAS.439L..21K/abstract
ADS Bibcode: 
2014MNRAS.439L..21K
Keywords: 
Catalogues; Galaxies: clusters: general; Galaxies: statistics; Large-scale structure of universe