Understanding the Core-Halo relation of quantum wave dark matter from 3D simulations
Journal
Physical Review Letters
Journal Volume
113
Journal Issue
26
Pages
261302
Date Issued
2014
Author(s)
Abstract
We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter, described by the Schrödinger-Poisson (SP) equation with a particle mass ∼10-22 eV. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass (Mc) and halo mass (Mh), Mca-1/2Mh1/3, where a is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of a statistical sample of virialized halos that form in our 3D cosmological simulations and by (ii) merging multiple solitons to create individual virialized objects. Sufficient simulation resolution is achieved by adaptive mesh refinement and graphic processing units acceleration. From this scaling relation, present dwarf satellite galaxies are predicted to have kiloparsec-sized cores and a minimum mass of ∼108M, capable of solving the small-scale controversies in the cold dark matter model. Moreover, galaxies of 2×1012M at z=8 should have massive solitonic cores of ∼2×109M within ∼60 pc. Such cores can provide a favorable local environment for funneling the gas that leads to the prompt formation of early stellar spheroids and quasars. © 2014 American Physical Society.
Other Subjects
Cosmology; Galaxies; Nonlinear equations; Poisson equation; Solitons; Adaptive mesh refinement; Cosmological structures; Graphic processing units; Local environments; Nonlinear structure; Scaling symmetries; Statistical samples; Uncertainty principles; Gravitation
Type
journal article