标题： 晕族各向异性属性的合并响应 显示英文标题

标题： Merger Response of Halo Anisotropy Properties

摘要： 各向异性属性——晕旋量、形状、位置偏移、速度偏移和取向——是一类重要的暗晕属性，它们反映了晕内部结构的方向变化程度。 这些属性反映晕的动力学状态，而动力学状态又取决于质量积累历史。 在这项工作中，我们利用IllustrisTNG模拟研究了各向异性属性随并合活动的演化。 我们发现，各向异性属性的响应轨迹显著偏离于恒定演化。 这些轨迹在广泛的并合和宿主属性范围内具有相同的定性特征和时间尺度。 我们提出了对这些属性行为的解释，并将其演化与并合动力学的相关阶段联系起来。 我们测量了相关的动力学时间尺度。 我们还探讨了响应强度随并合时间、并合比例和主晕质量的变化依赖关系。 这些结果为理解晕并合的物理机制及其对晕属性统计行为的影响提供了启示。 这项研究为进一步理解尺度关系的物理机制奠定了基础，特别是如何将它们的散射系统性与晕的质量积累历史联系起来。 显示英文摘要

摘要： Anisotropy properties -- halo spin, shape, position offset, velocity offset, and orientation -- are an important family of dark matter halo properties that indicate the level of directional variation of the internal structures of haloes. These properties reflect the dynamical state of haloes, which in turn depends on the mass assembly history. In this work, we study the evolution of anisotropy properties in response to merger activity using the IllustrisTNG simulations. We find that the response trajectories of the anisotropy properties significantly deviate from secular evolution. These trajectories have the same qualitative features and timescales across a wide range of merger and host properties. We propose explanations for the behaviour of these properties and connect their evolution to the relevant stages of merger dynamics. We measure the relevant dynamical timescales. We also explore the dependence of the strength of the response on time of merger, merger ratio, and mass of the main halo. These results provide insight into the physics of halo mergers and their effects on the statistical behaviour of halo properties. This study paves the way towards a physical understanding of scaling relations, particularly to how systematics in their scatter are connected to the mass assembly histories of haloes.