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arXiv · 2412.01307

Interpreting the Extremely Diffuse Stellar Distribution of the Nube Galaxy through Fuzzy Dark Matter

Yu-Ming Yang·Zhao-Chen Zhang·Xiao-Jun Bi·Peng-Fei Yin
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Abstract

Recent observations have uncovered a remarkably flat and extremely diffuse stellar distribution within the almost dark dwarf galaxy Nube, posing a challenge to the standard cold dark matter scenario. In this study, we employ numerical simulations to explore the possibility that this anomalous stellar distribution can be attributed to the dynamical heating effect of fuzzy dark matter (FDM). The relatively isolated location and low baryon fraction of Nube make it an ideal system for investigating this effect. Our findings indicate that by adopting a halo profile consistent with the dynamical mass estimation of Nube and an FDM particle mass on the order of $10^{-23}$ eV, the final 2D stellar distribution derived from simulation closely matches observational data. These results suggest that FDM could provide an explanation for the extremely diffuse stellar distribution of Nube.

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Yu-Ming Yang, Zhao-Chen Zhang, Xiao-Jun Bi, Peng-Fei Yin. 2024-12-02. Interpreting the Extremely Diffuse Stellar Distribution of the Nube Galaxy through Fuzzy Dark Matter. https://doi.org/10.3847/2041-8213%2Fadb7da

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