BAO reconstruction: a swift numerical action method for massive spectroscopic surveys
Abstract
A new fully non-linear reconstruction algorithm for the accurate recovery of the baryonic acoustic oscillations (BAO) scale in two-point correlation functions is proposed, based on the least action principle and extending the Fast Action Minimisation method by Nusser & Branchini (2000). Especially designed for massive spectroscopic surveys, it is tested on dark matter halo catalogues extracted from the DEUS-FUR Lambda cold dark matter simulation (Reverdy et al. 2015) to trace the trajectories of up to {∼ }207 000 haloes backward in time, well beyond the first-order Lagrangian approximation. The new algorithm successfully recovers the BAO feature in real and redshift space in both the monopole and the anisotropic two-point correlation function, also for anomalous samples showing misplaced or absent signature of BAO. In redshift space, the non-linear displacement parameter ΣNL is reduced from 11.8± 0.3 h^{-1} Mpc at redshift z = 0 to 4.0± 0.5 h^{-1} Mpc at z ≃ 37 after reconstruction. A comparison with the first-order Lagrangian reconstruction is presented, showing that these techniques outperform the linear approximation in recovering an unbiased measurement of the acoustic scale.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 2019
- DOI:
- 10.1093/mnras/stz278
- arXiv:
- arXiv:1809.10738
- Bibcode:
- 2019MNRAS.484.3818S
- Keywords:
-
- methods: numerical;
- cosmological parameters;
- large-scale structure of Universe;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 14 pages, 11 figures, submitted to MNRAS