2017/03/24(Fri) 14:00 -15:30 七樓研討室 7F, P7F Seminar Room
Title
Ultra-Light Axion Dark Matter and its impacts on dark halo structure in N-body simulation
Abstract
The Ultra-Light Axion (ULA) is a dark matter candidate with mass
O(10^-22)eV and de Broglie wavelength of order kpc.
Such an axion, also called the Fuzzy Dark Matter (FDM), thermalizes via the gravitational force and forms a Bose-Einstein condensate.
Recent studies suggested that the quantum pressure from the FDM
can significantly affect the structure formation in small scales, thus
alleviating the so-called ``small-scale crisis''.
In this paper, we develop a new technique to discretize the
quantum pressure and illustrate the interactions among FDM particles
in the N-body simulation, which accurately simulates the
formation of the dark-matter halo and its inner structure.
In a self-gravitationally-bound virialized halo, we find a constant density,
solitonic core, which is consistent with the theoretical prediction.
The existence of the solitonic core reveals the non-linear effect of quantum
pressure and impacts the structure formation in the FDM model.
Language
演講語言 (Language): in English
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