Kamionkowski M, Liddle AR. The dearth of halo dwarf galaxies: is there power on short scales?
PHYSICAL REVIEW LETTERS 2000;
84:4525-4528. [PMID:
10990731 DOI:
10.1103/physrevlett.84.4525]
[Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/1999] [Indexed: 05/23/2023]
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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