Multiwavelength scaling relations in galaxy groups: a detailed comparison of GAMA and KiDS observations to BAHAMAS simulations

Jakobs, A.; Viola, M.; McCarthy, I.; van Waerbeke, L.; Hoekstra, H.; Robotham, A.; Hinshaw, G.; Hojjati, A.; Tanimura, H.; Tröster, T.; Baldry, I.; Heymans, C.; Hildebrandt, H.; Kuijken, K.; Norberg, P.; Schaye, J.; Sifón, C.; van Uitert, E.; Valentijn, E.; Verdoes Kleijn, G.; Wang, L.

doi:10.1093/mnras/sty2017

Multiwavelength scaling relations in galaxy groups: a detailed comparison of GAMA and KiDS observations to BAHAMAS simulations

Jakobs, A.; Viola, M.; McCarthy, I.; van Waerbeke, L.; Hoekstra, H.; Robotham, A.; Hinshaw, G.; Hojjati, A.; Tanimura, H.; Tröster, T.; Baldry, I.; Heymans, C.; Hildebrandt, H.; Kuijken, K.; Norberg, P.; Schaye, J.; Sifón, C.; van Uitert, E.; Valentijn, E.; Verdoes Kleijn, G.; Wang, L.

Authors

A. Jakobs

M. Viola

I. McCarthy

L. van Waerbeke

H. Hoekstra

A. Robotham

G. Hinshaw

A. Hojjati

H. Tanimura

T. Tröster

I. Baldry

C. Heymans

H. Hildebrandt

K. Kuijken

Professor Peder Norberg peder.norberg@durham.ac.uk
Professor

J. Schaye

C. Sifón

E. van Uitert

E. Valentijn

G. Verdoes Kleijn

L. Wang

Abstract

We study the scaling relations between the baryonic content and total mass of groups of galaxies, as these systems provide a unique way to examine the role of non-gravitational processes in structure formation. Using Planck and ROSAT data, we conduct detailed comparisons of the stacked thermal Sunyaev-Zel’dovich (tSZ) and X-ray scaling relations of galaxy groups found in the Galaxy And Mass Assembly (GAMA) survey and the BAHAMAS hydrodynamical simulation. We use weak gravitational lensing data from the Kilo Degree Survey to determine the average halo mass of the studied systems. We analyse the simulation in the same way, using realistic weak lensing, X-ray, and tSZ synthetic observations. Furthermore, to keep selection biases under control, we employ exactly the same galaxy selection and group identification procedures to the observations and simulation. Applying this comparison, we find that the simulations reproduce the richness, size, and stellar mass functions of GAMA groups, as well as the stacked weak lensing and tSZ signals in bins of group stellar mass. However, the simulations predict X-ray luminosities that are higher than observed for this optically selected group sample. As the same simulations were previously shown to match the luminosities of X-ray-selected groups, this suggests that X-ray-selected systems may form a biased subset. Finally, we demonstrate that our observational processing of the X-ray and tSZ signals is free of significant biases. We find that our optical group selection procedure has, however, some room for improvement.

Citation

Jakobs, A., Viola, M., McCarthy, I., van Waerbeke, L., Hoekstra, H., Robotham, A., …Wang, L. (2018). Multiwavelength scaling relations in galaxy groups: a detailed comparison of GAMA and KiDS observations to BAHAMAS simulations. Monthly Notices of the Royal Astronomical Society, 480(3), 3338-3355. https://doi.org/10.1093/mnras/sty2017

Journal Article Type	Article
Acceptance Date	Jul 8, 2018
Online Publication Date	Jul 30, 2018
Publication Date	Nov 1, 2018
Deposit Date	Sep 24, 2018
Publicly Available Date	Sep 26, 2018
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	480
Issue	3
Pages	3338-3355
DOI	https://doi.org/10.1093/mnras/sty2017

Files

Published Journal Article (3.8 Mb)
PDF

Copyright Statement
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.