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arXiv · 2407.02991

Inner structure of dark matter halos at high $z$ in cosmological models with non-power-law primordial spectra

M. V. Tkachev·S. V. Pilipenko·E. V. Mikheeva·V. N. Lukash
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Abstract

We consider three cosmological models with non-power-law spectra of primordial density perturbations and test them against $\Lambda$CDM in density profiles of dark matter halos. We found that, despite the significant difference in initial conditions, the mean density profiles of all models are still close to the Navarro-Frenk-White one, albeit with some dispersion. We demonstrate that the density profile slopes in the innermost part of halo have a significant evolution with $z$, which can be used to identify the cosmological model. We also present a toy model resulting in the appearance of core in the central part of dark matter halo.

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M. V. Tkachev, S. V. Pilipenko, E. V. Mikheeva, V. N. Lukash. 2024-07-03. Inner structure of dark matter halos at high $z$ in cosmological models with non-power-law primordial spectra. https://doi.org/10.1103/physrevd.110.083530

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