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arXiv · 2502.20697

Stochastic lensing of stars by ultralight dark matter halos

Andrew Eberhardt·Elisa Ferreira·Wentao Luo·Shurui Lin·Yin Li
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Abstract

Ultralight dark matter is an interesting dark matter candidate describing the lightest end of the mass parameter space. This model produces an oscillating granular pattern in halo densities. These fluctuations have the potential to produce a time-varying density along the line of sight creating a small lensing signal for any stars observed through a dark matter halo which oscillates on the de Broglie timescale. In this work, we study this stochastic lensing signal taking into account the impact of density granules as well as the central soliton. We calculate the amplitude and temporal properties of this signal and estimate how stellar observations may be used to constrain the ultralight dark matter mass and abundance.

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Andrew Eberhardt, Elisa Ferreira, Wentao Luo, Shurui Lin, Yin Li. 2025-02-28. Stochastic lensing of stars by ultralight dark matter halos. https://arxiv.org/abs/2502.20697

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