Speaker
Description
Bosonic dark matter particles with hypothetical ultralight mass down to the order of a trillionth of an electronvolt have a de Borgolie wavelength in galactic length scales. The manifested quantum wave nature in astrophysical length scale suppresses and stabilizes the formation of small-scale structures with the uncertainty principle, and it is called fuzzy dark matter, which can be described by the Schrödinger-Poisson equation. Motivated by the concepts in atomic Bose-Einstein condensate, we examine the degree of spatial coherence of the field configuration in fuzzy dark matter halos. The compact soliton stabilized by the quantum pressure with a flat central density profile and full coherence sits at the centre of a halo and is surrounded by an incoherent field whose density follows the Navarro-Frenk-White profile and exhibits turbulent features. This spatial transition from coherence to incoherence can be well characterized by two parameters according to a generalized empirical core-halo profile, whose oscillations are found to be anti-correlated to the oscillation of the peak value of the power spectrum of the halo; their oscillation frequencies scale with the soliton core density. The outer halo reaches a quasi-steady state with a fixed distribution profile in the vortex energy spectrum, unveiling the vortical core structure, and the mean intervortex spacing is found to be correlated to the characteristic granule size.
We acknowledge funding from European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 897324 (upgradeFDM).
