Halo mass and weak galaxy–galaxy lensing profiles in rescaled cosmological N-body simulations. Issue 1 (18th May 2018)

• Record Type: Journal Article
• Authors: Renneby, Malin; Hilbert, Stefan; Angulo, Raúl E
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 479:Issue 1(2018)
• Page Start: 1100
• Page End: 1124
• Publication Date: 2018-05-18
• Subjects: gravitational lensing: weak -- methods: numerical -- galaxies: haloes -- cosmology: theory; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty1332
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: We investigate 3D density and weak lensing profiles of dark matter haloes predicted by a cosmology-rescaling algorithm for N -body simulations. We extend the rescaling method of Angulo & White and Angulo & Hilbert to improve its performance on intrahalo scales by using models for the concentration–mass–redshift relation based on excursion set theory. The accuracy of the method is tested with numerical simulations carried out with different cosmological parameters. We find that predictions for median density profiles are more accurate than ∼5 per cent for haloes with masses of 10 12.0 −10 14.5 h −1 M⊙ for radii 0.05 < r / r 200m < 0.5, and for cosmologies with Ωm ∈ [0.15, 0.40] and σ8 ∈ [0.6, 1.0]. For larger radii, 0.5 < r / r 200m < 5, the accuracy degrades to ∼20 per cent, due to inaccurate modelling of the cosmological and redshift dependence of the splashback radius. For changes in cosmology allowed by current data, the residuals decrease to ≲2 per cent up to scales twice the virial radius. We illustrate the usefulness of the method by estimating the mean halo mass of a mock galaxy group sample. We find that the algorithm's accuracy is sufficient for current data. Improvements in the algorithm, particularly in the modelling of baryons, are likely required for interpreting future (dark energy task force stage IV) experiments.