Einstein rings modulated by wavelike dark matter from anomalies in gravitationally lensed images
Journal
Nature Astronomy
Journal Volume
7
Journal Issue
6
Date Issued
2023-06-01
Author(s)
Amruth, Alfred
Broadhurst, Tom
Lim, Jeremy
Oguri, Masamune
Smoot, George F.
Diego, Jose M.
Leung, Enoch
Emami, Razieh
Li, Juno
Yeung, Michael C.H.
Li, Sung Kei
Abstract
Unveiling the true nature of dark matter, which manifests itself only through gravity, is one of the principal quests in physics. Leading candidates for dark matter are weakly interacting massive particles or ultralight bosons (axions), at opposite extremes in mass scales, that have been postulated by competing theories to solve deficiencies in the Standard Model of particle physics. Whereas dark matter weakly interacting massive particles behave like discrete particles (ϱDM), quantum interference between dark matter axions is manifested as waves (ψDM). Here, we show that gravitational lensing leaves signatures in multiply lensed images of background galaxies that reveal whether the foreground lensing galaxy inhabits a ϱDM or ψDM halo. Whereas ϱDM lens models leave well documented anomalies between the predicted and observed brightnesses and positions of multiply lensed images, ψDM lens models correctly predict the level of anomalies remaining with ϱDM lens models. More challengingly, when subjected to a battery of tests for reproducing the quadruply lensed triplet images in the system HS 0810+2554, ψDM is able to reproduce all aspects of this system whereas ϱDM often fails. The ability of ψDM to resolve lensing anomalies even in demanding cases such as HS 0810+2554, together with its success in reproducing other astrophysical observations, tilt the balance toward new physics invoking axions.
Type
journal article