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arXiv · 2408.00827

Diverse dark matter haloes in Two-field Fuzzy Dark Matter

Hoang Nhan Luu·Philip Mocz·Mark Vogelsberger·Alvaro Pozo·Tom Broadhurst·S. -H. Henry Tye·Tao Liu·Leo W. H. Fung·George F. Smoot·Razieh Emami·Lars Hernquist
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Abstract

Fuzzy dark matter (FDM) is a compelling candidate for dark matter, offering a natural explanation for the structure of diffuse low-mass haloes. However, the canonical FDM model with a mass of $10^{-22}~{\rm eV}$ encounters challenges in reproducing the observed diversity of dwarf galaxies, except for possibly scenarios where strong galactic feedback is invoked. The introduction of multiple-field FDM can provide a potential resolution to this diversity issue. The theoretical plausibility of this dark matter model is also enhanced by the fact that multiple axion species with logarithmically-distributed mass spectrum exist as a generic prediction of string theory. In this paper, we consider the axiverse hypothesis and investigate non-linear structure formation in the two-field fuzzy dark matter (2FDM) model. Our cosmological simulation with an unprecedented resolution and self-consistent initial conditions reveals the diverse structures of dark matter haloes in the 2FDM model for the first time. Depending on the formation time and local tidal activities, late-time haloes can host solitons of nested cores or solitons of one dominant species.

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Hoang Nhan Luu, Philip Mocz, Mark Vogelsberger, Alvaro Pozo, Tom Broadhurst, S. -H. Henry Tye, Tao Liu, Leo W. H. Fung, George F. Smoot, Razieh Emami, Lars Hernquist. 2024-08-01. Diverse dark matter haloes in Two-field Fuzzy Dark Matter. https://doi.org/10.1103/w9j1-k7b3

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