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arXiv · 2610.41522

Dark Halos, Intermediate-Mass BH and Nuclear Stellar Clusters in Dwarf Spheroidals

Rojin Bayati·Paolo Salucci
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Abstract

We exploit the halo densities of three dwarf spheroidals recently obtained to investigate their dark matter distribution. We address the well-known DM halo core-cusp issue by finding that the NFW $Λ$CDM halo profile is in strong disagreement with these inferred halo densities, which instead result very well-reproduced by the Burkert halo cored profile with the central density $ρ_0$ and the core radius $r_0$. These structural parameters result connected among themselves and with the length scale of the stellar matter component in a way similar to that present in disk systems. By analyzing the properties of dark halo densities in their innermost regions, we find no trace of a central intermediate-mass black hole or of a nuclear stellar cluster.

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Rojin Bayati, Paolo Salucci. 2026-10-30. Dark Halos, Intermediate-Mass BH and Nuclear Stellar Clusters in Dwarf Spheroidals. https://doi.org/10.3390/universe12070195

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