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arXiv · astro-ph/9911103

The dearth of halo dwarf galaxies: is there power on short scales?

Marc Kamionkowski·Andrew R. Liddle
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Abstract

N-body simulations of structure formation with scale-invariant primordial perturbations show significantly more virialized objects of dwarf-galaxy mass in a typical galactic halo than are observed around the Milky Way. We show that the dearth of observed dwarf galaxies could be explained by a dramatic downturn in the power spectrum at small distance scales. This suppression of small-scale power might also help mitigate the disagreement between cuspy simulated halos and smooth observed halos, while remaining consistent with Lyman-alpha-forest constraints on small-scale power. Such a spectrum could arise in inflationary models with broken scale invariance.

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Marc Kamionkowski, Andrew R. Liddle. 1999-11-06. The dearth of halo dwarf galaxies: is there power on short scales?. https://doi.org/10.1103/physrevlett.84.4525

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