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arXiv · 2412.20109

Employing shadow radius to constrain extra dimensions in black string space-time with dark matter halo

Zening Yan
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Abstract

We study the shadow of five-dimensional black strings immersed in dark matter environment. We show the influence of the momentum characteristic parameter $\widetilde{P_{y}}$ of the extra compact dimension on the shadow radius, and we provide the constraint range $0~\leq~\widetilde{P_{y}}~\lesssim~0.171215$ in the static Schwarzschild black string solution based on the observed data. Furthermore, we give the effective range $2.16138~\text{mm}~\lesssim~\ell~<~2.6~\text{mm}$ for the extra length $\ell$ and $\mathrm{k}~\lesssim~0.07398$ for the compactness parameter $\mathrm{k}$ in the environment near a black hole. We also find that the momentum characteristic parameter $\widetilde{P_{y}}$ of extra dimension will affect the effective range of dark matter related parameters when using shadow radius as a constraint tool.

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Zening Yan. 2024-12-28. Employing shadow radius to constrain extra dimensions in black string space-time with dark matter halo. https://arxiv.org/abs/2412.20109

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