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Unstable Cold Dark Matter and the Cuspy Halo Problem in Dwarf Galaxies

F. J. Sanchez-Salcedo
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Abstract

We speculate that the dark halos of dwarf galaxies and low surface brightness galaxies soften their central cusps by the decay of a fraction of cold dark matter (CDM) particles to a stable particle with a recoiling velocity of a few tens km s$^{-1}$, after they have driven the formation of galactic halos. This process, however, does not necessarily produce a significant reduction of the central dark matter density of satellite dwarf spheroidals like Draco or Fornax. It is shown that the recovered distribution of concentration parameters $c$ for the initial (before decay) Navarro-Frenk-White halos, is in good agreement with CDM predictions. Other interesting potentials of unstable CDM are highlighted.

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F. J. Sanchez-Salcedo. 2003-05-26. Unstable Cold Dark Matter and the Cuspy Halo Problem in Dwarf Galaxies. https://doi.org/10.1086/377092

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