波暗物質中的潮汐剝離和孤立子震盪

Abstract

波暗物質(Fuzzy Datter Matter,FDM)是一個有競爭力的暗物質候選理論，其在中心會有一個巨大的孤立子且有著大幅度密度震盪。先前的研究中指出即使周圍的暈被潮汐力給破壞掉，孤立子震盪依然存在。在本研究中我們經由自適應網格細化的三維波暗物質模擬展示了潮汐剝離是可以藉由移除孤立子的激發態去減緩震盪。減緩效率取決於軌道內主暈的平均密度和孤立子波峰密度的比率。此外當潮汐半徑相當於孤立子半徑時，孤立子就會被完全的被破壞。這些發現對於理論分析中心恆星物體因孤立子振盪所引起的加熱現象是重要的。

Fuzzy dark matter (FDM) is a strong dark matter candidate, featuring a massive central soliton with large-amplitude density oscillations. Previous studies suggested that the soliton oscillations persist even after the tidal disruption of a surrounding halo. Here, via three-dimensional FDM simulations with adaptive mesh refinement (AMR), we demonstrate that tidal stripping can damp soliton oscillations by removing the soliton excited states. The damping efficiency depends on the ratio between the average enclosed density of a host halo and the soliton peak density. Furthermore, a soliton can be completely disrupted if the tidal radius is comparable to the soliton radius. These findings are important for theoretical analyses of the heating of central stellar objects owing to soliton oscillations.