论文标题
通过太阳能磁通出现模拟在不同高度处的边界数据测试数据驱动的活动区域演变模型
Testing a Data-driven Active Region Evolution Model with Boundary Data at Different Heights from a Solar Magnetic Flux Emergence Simulation
论文作者
论文摘要
已经开发了一个数据驱动的活动区域演化（DARE）模型，以研究太阳冠状磁场的复杂结构和动力学。该模型由由强磁场控制的脆弱气体的典型冠状动脉环境配置，因此其下边界设置在电晕的底部，但由在光电球中观察到的磁场驱动。先前使用来自通量出现模拟（FES）数据的模型的评估表明，敢于在FES中重现冠状磁场，这归因于FES中FES中的光谱数据具有很强的Lorentz力量，因此在Dare模型中生成了极端的流量。在这里，我们通过使用从FES切成薄片的三组数据来进一步测试DARE，这与光球，色球和电晕的基部相对应。发现三组数据的关键区别是洛伦兹力的范围，这使数据驱动的模型的性能非常不同。在高于光球的两个较高级别的情况下，洛伦兹力量大大降低，而DARE模型的达到了与FES的更好一致，证明边界数据中的Lorentz力是影响DARE模型结果的关键问题。但是，与FES数据不同，最近发现来自SDO/HMI观测值的光电场非常接近无力。因此，我们建议将光球磁场用作冠状基座上的磁场以驱动DARE模型仍然是合理的。
A data-driven active region evolution (DARE) model has been developed to study the complex structures and dynamics of solar coronal magnetic fields. The model is configured with typical coronal environment of tenuous gas governed by strong magnetic field, and thus its lower boundary is set at the base of the corona, but driven by magnetic fields observed in the photosphere. A previous assessment of the model using data from a flux emergence simulation (FES) showed that the DARE failed to reproduce the coronal magnetic field in the FES, which is attributed to the fact that the photospheric data in the FES has a very strong Lorentz force and therefore spurious flows are generated in the DARE model. Here we further test the DARE by using three sets of data from the FES sliced at incremental heights, which correspond to the photosphere, the chromosphere and the base of the corona. It is found that the key difference in the three sets of data is the extent of the Lorentz force, which makes the data-driven model perform very differently. At the two higher levels above the photosphere, the Lorentz force decreases substantially, and the DARE model attains results in much better agreement with the FES, confirming that the Lorentz force in the boundary data is a key issue affecting the results of the DARE model. However, unlike the FES data, the photospheric field from SDO/HMI observations has recently been found to be very close to force-free. Therefore, we suggest that it is still reasonable to use the photospheric magnetic field as approximation of the field at the coronal base to drive the DARE model.
