Motion magnification in coronal seismology

Abstract

We introduce a new method for the investigation of low-amplitude transverse oscillations of solar plasma non-uniformities, such as coronal loops, individual strands in coronal arcades, jets, prominence fibrils, polar plumes, and other contrast features, observed with imaging instruments. The method is based on the two-dimensional dual tree complex wavelet transform (DT$\mathbb{C}$WT). It allows us to magnify transverse, in the plane-of-the-sky, quasi-periodic motions of contrast features in image sequences. The tests performed on the artificial data cubes imitating exponentially decaying, multi-periodic and frequency-modulated kink oscillations of coronal loops showed the effectiveness, reliability and robustness of this technique. The algorithm was found to give linear scaling of the magnified amplitudes with the original amplitudes provided they are sufficiently small. Also, the magnification is independent of the oscillation period in a broad range of the periods. The application of this technique to SDO/AIA EUV data cubes of a non-flaring active region allowed for the improved detection of low-amplitude decay-less oscillations in the majority of loops.

Accepted for publication in Solar Physics

References in corpus (3)

• Advances in Observing Various Coronal EUV Waves in the SDO Era and Their Seismological Applications (Invited Review)
• First direct measurements of transverse waves in solar polar plumes using SDO/AIA
• Coronal Fourier power spectra: implications for coronal seismology and coronal heating

Cited by in corpus (9)

• Kink oscillations of coronal loops
• Excitation of decay-less transverse oscillations of coronal loops by random motions
• Decayless oscillations in solar coronal bright points
• Magnetohydrodynamic Seismology of Quiet Solar Active Regions
• Flare induced decay-less transverse oscillations in solar coronal loops
• Two-Spacecraft Detection of Short-period Decayless Kink Oscillations of Solar Coronal Loops
• Novel data analysis techniques in coronal seismology
• 30-min Decayless Kink Oscillations in a Very Long Bundle of Solar Coronal Plasma Loops
• Microwave response to kink oscillations of a plasma slab