Galaxy-galaxy lensing in EAGLE: comparison with data from 180 deg² of the KiDS and GAMA surveys

Velliscig, M.; Cacciato, M.; Hoekstra, H.; Schaye, J.; Heymans, C.; Hildebrandt, H.; Loveday, J.; Norberg, P.; Sifïn, C.; Schneider, P.; van Uitert, E.; Viola, M.; Brough, S.; Erben, T.; Holwerda, B.W.; Hopkins, A.M.; Kuijken, K.

Abstract

We present predictions for the galaxy–galaxy lensing (GGL) profile from the EAGLE hydrodynamical cosmological simulation at redshift z = 0.18, in the spatial range 0.02 < R/(h− 1 Mpc) < 2, and for five logarithmically equispaced stellar mass bins in the range 10.3 < log10(Mstar/ M⊙) < 11.8. We compare these excess surface density profiles to the observed signal from background galaxies imaged by the Kilo Degree Survey around spectroscopically confirmed foreground galaxies from the Galaxy And Mass Assembly (GAMA) survey. Exploiting the GAMA galaxy group catalogue, the profiles of central and satellite galaxies are computed separately for groups with at least five members to minimize contamination. EAGLE predictions are in broad agreement with the observed profiles for both central and satellite galaxies, although the signal is underestimated at R ≈ 0.5–2 h− 1 Mpc for the highest stellar mass bins. When central and satellite galaxies are considered simultaneously, agreement is found only when the selection function of lens galaxies is taken into account in detail. Specifically, in the case of GAMA galaxies, it is crucial to account for the variation of the fraction of satellite galaxies in bins of stellar mass induced by the flux-limited nature of the survey. We report the inferred stellar-to-halo mass relation and we find good agreement with recent published results. We note how the precision of the GGL profiles in the simulation holds the potential to constrain fine-grained aspects of the galaxy-dark matter connection.

Citation

Velliscig, M., Cacciato, M., Hoekstra, H., Schaye, J., Heymans, C., Hildebrandt, H., …Kuijken, K. (2017). Galaxy-galaxy lensing in EAGLE: comparison with data from 180 deg² of the KiDS and GAMA surveys. Monthly Notices of the Royal Astronomical Society, 471(3), 2856-2870. https://doi.org/10.1093/mnras/stx1789

• Journal Article Type: Article
• Acceptance Date: Jul 13, 2017
• Online Publication Date: Jul 15, 2017
• Publication Date: Jul 15, 2017
• Deposit Date: Aug 29, 2017
• Publicly Available Date: Aug 31, 2017
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 471
• Issue: 3
• Pages: 2856-2870
• DOI: https://doi.org/10.1093/mnras/stx1789
• Public URL: https://durham-repository.worktribe.com/output/1346427