Disentangling redshift-space distortions and non-linear bias using the 2D power spectrum. Issue 1 (28th January 2016)

• Record Type: Journal Article
• Authors: Jennings, Elise; Wechsler, Risa H.; Skillman, Samuel W.; Warren, Michael S.
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 457:Issue 1(2016)
• Page Start: 1076
• Page End: 1088
• Publication Date: 2016-01-28
• Subjects: cosmology: theory -- large-scale structure of Universe; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stv2989
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We present the 2D redshift-space galaxy power spectrum, P ( k, μ), measured from the Dark Sky simulations, using catalogues constructed with halo occupation distribution and subhalo abundance matching methods, chosen to represent an intermediate redshift sample of luminous red galaxies. We find that the information content in individual μ (cosine of the angle to the line of sight) bins is substantially richer then multipole moments, and show that this can be used to isolate the impact of non-linear growth and redshift-space distortion (RSD) effects. Using the μ < 0.2 simulation data, which is not impacted by RSD, we can successfully measure the non-linear bias to ∼5 per cent at k < 0.6 h Mpc −1 . Using the low μ simulation data to constrain the non-linear bias, and μ ≥ 0.2 to constrain the growth rate, we show that f can be constrained to ∼26(22) per cent to a k max < 0.4(0.6) h Mpc −1 from clustering alone using a dispersion model, for a range of galaxy models. Our analysis of individual μ bins reveals interesting physical effects which arise from different methods of populating haloes with galaxies. We find a prominent turnaround scale, at which RSD damping effects are greater than the non-linear growth, which differs for each galaxy model. The idea of separating non-linear growth and RSD effects making use of the full information in the 2D galaxy power spectrum yields significant improvements in constraining cosmological parameters and may be a promising probe of galaxy formation models.