Testing the consistency of three-point halo clustering in Fourier and configuration space. Issue 1 (24th January 2018)

• Record Type: Journal Article
• Authors: Hoffmann, K; Gaztañaga, E; Scoccimarro, R; Crocce, M
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 476:Issue 1(2018)
• Page Start: 814
• Page End: 829
• Publication Date: 2018-01-24
• Subjects: methods: analytical -- methods: numerical -- methods: statistical -- large-scale structure of Universe; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty187
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We compare reduced three-point correlations Q of matter, haloes (as proxies for galaxies) and their cross-correlations, measured in a total simulated volume of ∼100 ( h −1 Gpc) 3, to predictions from leading order perturbation theory on a large range of scales in configuration space. Predictions for haloes are based on the non-local bias model, employing linear ( b 1 ) and non-linear ( c 2, g 2 ) bias parameters, which have been constrained previously from the bispectrum in Fourier space. We also study predictions from two other bias models, one local ( g 2 = 0) and one in which c 2 and g 2 are determined by b 1 via approximately universal relations. Overall, measurements and predictions agree when Q is derived for triangles with ( r 1 r 2 r 3 ) 1/3 ≳60 h −1 Mpc, where r 1 − 3 are the sizes of the triangle legs. Predictions for Q matter, based on the linear power spectrum, show significant deviations from the measurements at the BAO scale (given our small measurement errors), which strongly decrease when adding a damping term or using the non-linear power spectrum, as expected. Predictions for Q halo agree best with measurements at large scales when considering non-local contributions. The universal bias model works well for haloes and might therefore be also useful for tightening constraints on b 1 from Q in galaxy surveys. Such constraints are independent of the amplitude of matter density fluctuation (σ8 ) and hence break the degeneracy between b 1 and σ8, present in galaxy two-point correlations.