AI 中文总结
本研究借助SUNRISE III/SCIP的SCIP观测数据，证实宁静太阳中向色球层膨胀的通量管可作为磁声通道，使低频波向上传播并驱动色球层动力学。
AI 中文摘要
声波向色球层传播，对能量传输及其动力学过程有重要贡献，其向上传播仅限于高于声学截止频率的频段。磁场结构在决定声波能否向上传播中起关键作用，因为在磁场相对于重力倾斜的区域，截止频率会降低，从而形成所谓的磁声通道。此前的研究已将宁静区的磁场与振荡关联起来，但这些分析基于光球层的磁场信息，未对色球层结构进行约束。本研究利用光球层数据，并首次采用2024年发射的气球载太阳观测站Sunrise III上搭载的Sunrise色球层红外光谱偏振仪（SCIP）获取的宁静区色球层光谱偏振数据，研究声波与磁场拓扑结构之间的耦合关系。SCIP的凝视观测采样了这样的磁特征：光球层中视线方向的磁场强度呈现多个尖锐的空间峰值，而在色球层的两个高度处，磁场变得更宽且更弱，表明存在膨胀的通量管。这些通量管中的色球层速度场呈现强烈的5分钟振荡，而周围区域则显示微弱的3分钟振荡。在这些通量管中，锯齿状的时间速度变化与强度增强相关，表明存在陡化的激波。具有低频振荡的通量管不仅在网络区域被识别，也在弱网络间区域被识别。这些结果提供了观测证据，证明在网络区域和弱网络间区域，向色球层膨胀的通量管可作为磁声通道，允许低频波向上传播，并通过激波驱动色球层动力学。
英文摘要
Acoustic waves propagate into the chromosphere, contributing to energy transport and their dynamics. Their upward propagation is restricted to frequencies above the acoustic cutoff frequency. The magnetic field configuration plays a key role in determining whether acoustic waves can propagate upward because the cutoff frequency is reduced in regions where the field is inclined with respect to gravity, forming so-called magnetoacoustic portals. Previous studies linked magnetic fields and oscillations in quiet regions, but these analyses were based on photospheric magnetic field information, leaving chromospheric structure unconstrained. This study investigates the coupling between acoustic waves and magnetic topology using photospheric and, for the first time, chromospheric spectropolarimetry in a quiet region, obtained with the Sunrise Chromospheric Infrared SpectroPolarimeter (SCIP) aboard the Sunrise iii balloon-borne solar observatory launched in 2024. The SCIP sit-and-stare observations sampled magnetic features in which the line-of-sight field strength exhibits multiple sharp spatial peaks in the photosphere while becoming broader and weaker at two heights in the chromosphere, indicating expanding fluxtubes. The chromospheric velocity field in these fluxtubes exhibits strong 5-minute oscillations, while the surrounding regions show weak 3-minute oscillations. In these fluxtubes, sawtooth temporal velocity variations are associated with intensity enhancements, suggesting steepened shocks. Fluxtubes with low-frequency oscillations are identified not only in network regions but also in weak internetwork regions. These results provide observational evidence that fluxtubes expanding into the chromosphere act as magnetoacoustic portals, in both network and internetwork regions, allowing low-frequency waves to propagate upward and driving chromospheric dynamics via shocks.
Comments11 pages, 3 figures, accepted
