活动区周围的地震晕：一个MHD理论
Seismic Halos Around Active Regions: An MHD Theory
摘要：
理解磁场影响传播波的方式是构建活动区地下结构和动力学的精确日震模型的第一步。在这里，我们提出了一种数值方法来计算的线性相互作用的波与磁场嵌入在一个类似太阳的分层背景。理想的磁流体动力学（MHD）方程组求解的三维盒子，跨越太阳光球，从35毫米内延伸到1.2毫米到大气中。在执行这些模拟的挑战之一涉及生成磁流体静力（MHS）状态，其中分层假设水平的不均匀性，除了强垂直分层与近地层。记住，这一努力的目的是了解和表征线性MHD相互作用，我们讨论了一种方法计算静态一致的背景状态。功率图计算的波与厚通量管的峰值光球场强度600 G和3000 G的模拟相互作用。在厚通量管的模拟中，可以看到通量管的“本影”区域中被波功率增加的光晕包围的强模态功率降低。这些增强也可以在太阳活动区域的多普勒速度功率图中看到，这使我们提出晕有MHD的基础。
英文摘要：
Comprehending the manner in which magnetic fields affect propagating waves is a first step toward constructing accurate helioseismic models of active region sub-surface structure and dynamics. Here, we present a numerical method to compute the linear interaction of waves with magnetic fields embedded in a solar-like stratified background. The ideal Magneto-Hydrodynamic (MHD) equations are solved in a 3-dimensional box that straddles the solar photosphere, extending from 35 Mm within to 1.2 Mm into the atmosphere. One of the challenges in performing these simulations involves generating a Magneto-Hydro-Static (MHS) state wherein the stratification assumes horizontal inhomogeneity in addition to the strong vertical stratification associated with the near-surface layers. Keeping in mind that the aim of this effort is to understand and characterize linear MHD interactions, we discuss a means of computing statically consistent background states. Power maps computed from simulations of waves interacting with thick flux tubes of peak photospheric field strengths 600 G and 3000 G are presented. Strong modal power reduction in the `umbral' regions of the flux tube enveloped by a halo of increased wave power are seen in the simulations with the thick flux tubes. These enhancements are also seen in Doppler velocity power maps of active regions observed in the Sun, leading us to propose that the halo has MHD underpinnings.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
