星系过程引起的磁生成：对星系周和星系际磁场的影响
Magnetogenesis by galactic processes: impact on circumgalactic and intergalactic fields
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中文总结 AI 辅助
利用宇宙学磁流体动力学模拟研究宇宙磁场起源演化，在IllustrisTNG模型基础上实施磁生成方法，比较不同播种模型，发现磁场拓扑差异及反馈驱动注入的作用，还探讨了星系际介质中磁场情况及高红移约束问题。
中文摘要 AI 辅助
我们使用移动网格代码AREPO运行的一系列大体积宇宙学磁流体动力学模拟（L$_\mathrm{box}=25$ Mpc/h）来研究宇宙磁场的起源和演化。在IllustrisTNG星系形成模型之上，我们实施了额外的磁生成方法，即在超新星（SNe）和超大质量黑洞（SMBH）反馈事件期间注入磁能，并将这些与用均匀原始种子场初始化的模拟进行比较。在不同播种模型中，$z = 0$时晕磁场强度大致相似，主要由小尺度和晕尺度的发电机作用放大和维持。然而，我们发现磁场拓扑存在差异，SMBH驱动的模型显示出比仅原始场和仅SNe运行系统地更小的相干长度。我们发现反馈驱动的注入加速了发电机增长的开始，导致磁场强度随数值分辨率更快地收敛，特别是在低质量晕中。在星系际介质（IGM）中，仅SNe注入在$z = 0$和$z \sim 3$时相对于从γ射线级联约束推断的下限产生的磁场不足，而我们基于特定SMBH的注入处方满足当前约束，但在高红移时仍存在轻微紧张关系。因此，协调这些特定的高红移约束可能需要修改反馈处方或额外的原始播种成分。
英文摘要
We investigate the origin and evolution of cosmic magnetic fields using a suite of large-volume cosmological magnetohydrodynamic simulations (L$_\mathrm{box}=25$ Mpc/h) run with the moving-mesh code AREPO. Atop the IllustrisTNG galaxy formation model, we implement additional recipes for magnetogenesis in which magnetic energy is injected during supernovae (SNe) and supermassive black hole (SMBH) feedback events, and compare these to simulations initialized with uniform primordial seed fields. Halo magnetic field strengths at $z=0$ are largely similar across seeding models and are primarily amplified and sustained by small-scale and halo-scale dynamo action. Nevertheless, we find differences in magnetic field topology, with SMBH-driven models exhibiting systematically smaller coherence lengths than primordial-only and SNe-only runs. We find that feedback-driven injection accelerates the onset of dynamo growth, leading to more rapid convergence of magnetic field strengths with numerical resolution, particularly in low-mass halos. In the intergalactic medium (IGM), SNe-only injection underproduces magnetic fields relative to inferred lower limits from $γ$-ray cascade constraints at both $z=0$ and $z \sim 3$, whereas our specific SMBH-based injection prescription satisfies present-day constraints but remains in mild tension at high redshifts. Reconciling these specific high-$z$ constraints therefore likely requires either modified feedback prescriptions or an additional primordial seeding component.
