Title: Cosmological zoom-in simulation of fuzzy dark matter down to z = 0: tidal evolution of subhaloes in a Milky Way-sized halo Show Chinese title

Title: 模糊暗物质的宇宙学放大模拟至 z = 0：银河系大小晕团中次晕的潮汐演化

Abstract: Subhaloes are critical in distinguishing dark matter models, yet their evolution within galactic haloes, particularly in the Fuzzy Dark Matter (FDM) model, remains challenging to fully investigate in numerical simulations. In this work, we employ the fluid-wave hybrid scheme recently implemented in the GAMER-2 code to perform a cosmological zoom-in simulation of a Milky Way-sized halo with an FDM particle mass of m = 2 x 10^(-23) eV. It simultaneously resolves the solitonic core of the host halo and tracks the complex tidal evolution of subhaloes down to redshift z = 0. We examine the internal structure of subhaloes by analyzing their density profiles, velocity dispersions, and density power spectra across various redshifts. Our findings show that partially tidally stripped subhaloes deviate from the core-halo mass relation; their solitons remain intact and are enveloped by smaller granules predominantly from the host halo. Furthermore, our simulation unravels a complex tidal evolution of FDM subhaloes. On the one hand, we observe a subhalo core undergoing complete tidal disruption at z ~ 0.14, which later reemerges near the outskirts of the host halo around z ~ 0. This disruption event, characterized by a core contaminated with interference fringes from the host halo's wave function, occurs earlier than previously predicted. On the other hand, FDM subhaloes have denser cores before infall due to the presence of central solitons, making them more resilient to tidal disruption than their N-body counterparts. Our results demonstrate GAMER-2's capability to resolve non-linear FDM substructure down to z = 0, paving the way for future studies of larger FDM subhalo samples with heavier particle masses. The simulation code GAMER-2 and the simulation setup used in this work are available at https://github.com/gamer-project/gamer. Show Chinese abstract

Abstract: 亚晕在区分暗物质模型中起着关键作用，然而它们在星系晕内的演化，特别是在模糊暗物质（FDM）模型中的演化，仍难以在数值模拟中完全研究。 在本工作中，我们采用最近在GAMER-2代码中实现的流体波混合方案，对一个银河系大小的晕进行宇宙学缩放模拟，其中FDM粒子质量为m = 2 x 10^(-23) eV。 它同时解析宿主晕的孤子核心，并追踪亚晕在红移z = 0处的复杂潮汐演化。 我们通过分析不同红移下的密度剖面、速度弥散和密度功率谱来研究亚晕的内部结构。 我们的研究结果表明，部分潮汐剥离的亚晕偏离了核心-晕质量关系；它们的孤子保持完整，并被主要来自宿主晕的小颗粒包围。 此外，我们的模拟揭示了FDM亚晕的复杂潮汐演化。 一方面，我们观察到一个亚晕核心在z ~ 0.14处经历完全的潮汐破坏，随后在z ~ 0附近重新出现在宿主晕的边缘。 这次破坏事件，其核心被宿主晕波函数的干涉条纹污染，比之前预测的发生时间更早。 另一方面，由于中心孤子的存在，FDM亚晕在落入前具有更致密的核心，使其比N体对应物更能抵抗潮汐破坏。 我们的结果展示了GAMER-2解析非线性FDM次结构到z = 0的能力，为未来研究更大质量的FDM亚晕样本奠定了基础。 模拟代码GAMER-2以及本工作中使用的模拟设置可在https://github.com/gamer-project/gamer获取。