Proper Orthogonal and Dynamic Mode Decomposition of Sunspot Data

Abstract

High resolution solar observations show the complex structure of the magnetohydrodynamic (MHD) wave motion. We apply the techniques of POD and 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.

References in corpus (8)

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Cited by in corpus (8)

• Waves in the lower solar atmosphere: the dawn of next-generation solar telescopes
• The Propagation of Coherent Waves Across Multiple Solar Magnetic Pores
• A novel approach to identify resonant MHD wave modes in solar pores and sunspot umbrae: $B-\omega$ analysis
• Magnetohydrodynamic wave mode identification in circular and elliptical sunspot umbrae: evidence for high order modes
• Dynamic mode decomposition of magnetohydrodynamic bubble chain flow in a rectangular vessel
• High-resolution wave dynamics in the lower solar atmosphere
• Origin of the Chromospheric Umbral Waves in Sunspots
• Multi-height Identification of Sausage and Fluting Eigenmodes in a Solar Pore