Small-scale magnetic fields in the solar atmosphere

太阳大气中的小尺度磁场

• 批准号: 30717509
• 负责人: Professor Dr. Wolfgang Schmidt
• 金额: --
• 依托单位: Institut für Sonnenphysik (KIS)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/30717509?language=en
• 关键词: Small; scale; magnetic; fields; solar

Small-scale magnetic structures in the photosphere of the sun play a key role for the solar irradiance variability as well as for the energy transport to the corona. Most magnetic flux concentrations are visible as bright round or elongated objects with a magnetic field strength of about 0.1 T. In this project we intend to observe the magnetic field, the plasma motion and the intensity as a function of time of various kinds of small magnetic elements. The study of their formation, evolution and disappearance will provide insight in basic magneto-convective processes that take place on the sun. With imultaneous measurements of magnetic and flow field we aim to answer how the magnetic flux is concentrated to its observed value and how it decays again. At the same time, we seek to understand how the magnetic flux is brought to the solar surface and how it disappears again. We use high-precision spectro-polarimetry to measure the magnetic field at a spatial resolution down to 0.25 arcs (160 km on the sun) by using spectro-polarimeters at the German Vacuum Tower Telescope. These instruments permit simultaneous observation in several spectral bands in the visible and the near UV. In order to derive the magnetic field and other physical quantities from the data, we will employ pectral line inversion techniques. Our results will be compared to predictions from numerical simulations and will provide important boundary conditions for theoretical and numerical models.

太阳光球层中的小尺度磁性结构对于太阳辐照度变化以及向日冕的能量传输起着关键作用。大多数磁通量集中表现为明亮的圆形或细长物体，磁场强度约为 0.1 T。在这个项目中，我们打算观察磁场、等离子体运动以及各种小型磁性元件随时间变化的强度。对它们的形成、演化和消失的研究将为了解太阳上发生的基本磁对流过程提供见解。通过同时测量磁场和流场，我们的目标是回答磁通量如何集中到其观测值以及它如何再次衰减。与此同时，我们试图了解磁通量如何被带到太阳表面以及如何再次消失。我们通过德国真空塔望远镜上的分光偏振计，使用高精度分光偏振测量仪来测量磁场，空间分辨率低至 0.25 弧度（距离太阳 160 公里）。这些仪器允许同时观察可见光和近紫外光的多个光谱带。为了从数据中导出磁场和其他物理量，我们将采用谱线反演技术。我们的结果将与数值模拟的预测进行比较，并将为理论和数值模型提供重要的边界条件。