AI 中文总结
本研究通过高分辨率数值模拟，探究多场模糊暗物质晕的波结构动力学，发现场数增加会抑制颗粒的动力学加热，且中心核贡献会削弱该抑制趋势。
AI 中文摘要
作为单场模糊暗物质（FDM）模型的自然扩展，多场FDM近年来受到越来越多的关注。该场景既源于弦理论预测的轴子景（axiverse）场景，也源于多场FDM可能比其单场对应模型更符合天体物理观测的可能性。在本研究中，我们开展高分辨率数值模拟，系统探究多场FDM晕中波结构的动力学，具体研究中心核的振荡与随机运动、颗粒的演化及统计特性，以及由此对嵌入其中的恒星系统产生的动力学加热。我们发现，与单场情况相比，中心核密度振荡的频谱会出现多个峰值，并向更高频率偏移；不同场分量的中心会经历近乎同步的随机游走，而次主导分量则表现出更大的随机游走动幅。我们进一步表明，在较宽参数范围内，颗粒密度波动随场数增加而受到的抑制，对各分量的丰度占比基本不敏感。此外，通过自洽模拟，我们发现颗粒诱导的动力学加热会随场数增加而逐渐被抑制，但一旦考虑中心核的贡献，这一趋势会变得明显平缓。
英文摘要
As a natural extension of the single-field fuzzy dark matter (FDM) model, multifield FDM has attracted increasing attention in recent years. This scenario is motivated both by the axiverse scenario predicted by string theory and by the possibility that multifield FDM may provide a better match to astrophysical observations than its single-field counterpart. In this work, we perform high-resolution numerical simulations to systematically investigate the dynamics of wave structures in multifield FDM halos. In particular, we study the oscillatory and stochastic motions of the central core, the evolution and statistical properties of granules, and the resulting dynamical heating of embedded stellar systems. We find that the frequency spectra of the core density oscillations develop multiple peaks and shift toward higher frequencies relative to the single-field case. The centers of different field components undergo nearly synchronized random walks, while subdominant components exhibit larger random-walk amplitudes. We further show that the suppression of granule density fluctuations with increasing number of fields is largely insensitive to the fractional abundance of each component over a broad parameter range. Moreover, using self-consistent simulations, we find that the dynamical heating induced by granules is progressively suppressed as the number of fields increases. However, once the contribution from the central core is taken into account, this trend would become much less pronounced.
Comments12 pages, 11 figures
