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arXiv · 2406.08537

A high-resolution view of the source-plane magnification near cluster caustics in wave dark matter models

Jose M. Diego·Alfred Amruth·Jose M. Palencia·Tom Broadhurst·Sung Kei Li·Jeremy Lim·Rogier A. Windhorst·Adi Zitrin·Alexei V. Filippenko·Liliya L. R. Williams·Ashish K. Meena·Wenlei Chen·Patrick L. Kelly
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Abstract

We present the highest resolution images to date of caustics formed by wave dark matter ($\psi$DM) fluctuations near the critical curves of cluster gravitational lenses. We describe the basic magnification features of $\psi$DM in the source plane at high macromodel magnification and discuss specific differences between the $\psi$DM and standard cold dark matter (CDM) models. The unique generation of demagnified counterimages formed outside the Einstein radius for $\psi$DM is highlighted. Substructure in CDM cannot generate such demagnified images of positive parity, thus providing a definitive way to distinguish $\psi$DM from CDM. Highly magnified background sources with sizes $r\approx 1pc$, or approximately a factor of ten smaller than the expected de Broglie wavelength of $\psi$DM, offer the best possibility of discriminating between $\psi$DM and CDM. These include objects such as very compact stellar clusters at high redshift that JWST is finding in abundance.

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Jose M. Diego, Alfred Amruth, Jose M. Palencia, Tom Broadhurst, Sung Kei Li, Jeremy Lim, Rogier A. Windhorst, Adi Zitrin, Alexei V. Filippenko, Liliya L. R. Williams, Ashish K. Meena, Wenlei Chen, Patrick L. Kelly. 2024-06-12. A high-resolution view of the source-plane magnification near cluster caustics in wave dark matter models. https://doi.org/10.1051/0004-6361/202451246

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