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Title: A stringent upper limit on dark matter self-interaction cross-section from cluster strong lensing
ABSTRACT

We analyse strongly lensed images in eight galaxy clusters to measure their dark matter density profiles in the radial region between 10 kpc and 150 kpc, and use this to constrain the self-interaction cross-section of dark matter (DM) particles. We infer the mass profiles of the central DM haloes, bright central galaxies, key member galaxies, and DM subhaloes for the member galaxies for all eight clusters using the qlens code. The inferred DM halo surface densities are fit to a self-interacting dark matter model, which allows us to constrain the self-interaction cross-section over mass σ/m. When our full method is applied to mock data generated from two clusters in the Illustris-TNG simulation, we find results consistent with no dark matter self-interactions as expected. For the eight observed clusters with average relative velocities of $1458_{-81}^{+80}$ km s−1, we infer $\sigma /m = 0.082_{-0.021}^{+0.027} \rm cm^2\, g^{ -1}$ and $\sigma /m \lt 0.13~ \rm cm^2\, g^{ -1}$ at the 95 per cent confidence level.

 
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Award ID(s):
1831412 1915005
NSF-PAR ID:
10379839
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
510
Issue:
1
ISSN:
0035-8711
Page Range / eLocation ID:
p. 54-81
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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