Albidah A B, Brevis W, Fedun V, Ballai I, Jess D B, Stangalini M, Higham J, Verth G
Plasma Dynamics Group, School of Mathematics and Statistics, The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, UK.
Department of Mathematics, College of Science Al-Zulfi, Majmaah University, Al-Majmaah, Saudi Arabia.
Philos Trans A Math Phys Eng Sci. 2021 Feb 8;379(2190):20200181. doi: 10.1098/rsta.2020.0181. Epub 2020 Dec 21.
High-resolution solar observations show the complex structure of the magnetohydrodynamic (MHD) wave motion. We apply the techniques of proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) to identify the dominant MHD wave modes in a sunspot using the intensity time series. The POD technique was used to find modes that are spatially orthogonal, whereas the DMD technique identifies temporal orthogonality. Here, we show that the combined POD and DMD approaches can successfully identify both sausage and kink modes in a sunspot umbra with an approximately circular cross-sectional shape. This article is part of the Theo Murphy meeting issue 'High-resolution wave dynamics in the lower solar atmosphere'.
高分辨率太阳观测揭示了磁流体动力学（MHD）波运动的复杂结构。我们应用本征正交分解（POD）和动态模式分解（DMD）技术，利用强度时间序列来识别太阳黑子中占主导地位的MHD波模式。POD技术用于寻找空间正交的模式，而DMD技术则识别时间正交性。在此，我们表明，POD和DMD相结合的方法能够成功识别出横截面形状近似圆形的太阳黑子本影中的腊肠模和扭结模。本文是西奥·墨菲会议文集“太阳低层大气中的高分辨率波动动力学”的一部分。
