Observable tests of self-interacting dark matter in galaxy clusters: cosmological simulations with SIDM and baryons

Robertson, Andrew; Harvey, David; Massey, Richard; Eke, Vincent; McCarthy, Ian G.; Jauzac, Mathilde; Li, Baojiu; Schaye, Joop

doi:10.1093/mnras/stz1815

Observable tests of self-interacting dark matter in galaxy clusters: cosmological simulations with SIDM and baryons

Robertson, Andrew; Harvey, David; Massey, Richard; Eke, Vincent; McCarthy, Ian G.; Jauzac, Mathilde; Li, Baojiu; Schaye, Joop

Authors

Andrew Robertson

David Harvey

Professor Richard Massey r.j.massey@durham.ac.uk
Professor

Dr Vincent Eke v.r.eke@durham.ac.uk
Associate Professor

Ian G. McCarthy

Professor Mathilde Jauzac mathilde.jauzac@durham.ac.uk
Professor

Professor Baojiu Li baojiu.li@durham.ac.uk
Professor

Joop Schaye

Abstract

We present BAHAMAS-SIDM, the first large-volume, (400 h−1 Mpc)3, cosmological simulations including both self-interacting dark matter (SIDM) and baryonic physics. These simulations are important for two primary reasons: 1) they include the effects of baryons on the dark matter distribution 2) the baryon particles can be used to make mock observables that can be compared directly with observations. As is well known, SIDM haloes are systematically less dense in their centres, and rounder, than CDM haloes. Here we find that that these changes are not reflected in the distribution of gas or stars within galaxy clusters, or in their X-ray luminosities. However, gravitational lensing observables can discriminate between DM models, and we present a menu of tests that future surveys could use to measure the SIDM interaction strength. We ray-trace our simulated galaxy clusters to produce strong lensing maps. Including baryons boosts the lensing strength of clusters that produce no critical curves in SIDM-only simulations. Comparing the Einstein radii of our simulated clusters with those observed in the CLASH survey, we find that at velocities around 1000 km s−1 an SIDM cross-section of σ/m ≳ 1 cm2 g−1 is likely incompatible with observed cluster lensing.

Citation

Robertson, A., Harvey, D., Massey, R., Eke, V., McCarthy, I. G., Jauzac, M., …Schaye, J. (2019). Observable tests of self-interacting dark matter in galaxy clusters: cosmological simulations with SIDM and baryons. Monthly Notices of the Royal Astronomical Society, 488(3), 3646-3662. https://doi.org/10.1093/mnras/stz1815

Journal Article Type	Article
Acceptance Date	Oct 12, 2018
Online Publication Date	Jul 10, 2019
Publication Date	Sep 30, 2019
Deposit Date	Dec 11, 2018
Publicly Available Date	Jul 18, 2019
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	488
Issue	3
Pages	3646-3662
DOI	https://doi.org/10.1093/mnras/stz1815
Related Public URLs	https://arxiv.org/abs/1810.05649