Time-dependent suppression of oscillatory power in evolving solar magnetic fields

Abstract

Oscillation amplitudes are generally smaller within magnetically active regions like sunspots and plage, when compared to their surroundings. Such magnetic features, when viewed in spatially-resolved powermaps, appear as regions of suppressed power due to reductions in the oscillation amplitudes. Employing high spatial- and temporal-resolution observations from the Dunn Solar Telescope (DST) in New Mexico, we study the power suppression in a region of evolving magnetic fields adjacent to a pore. By utilising wavelet analysis, we study for the first time, how the oscillatory properties in this region change as the magnetic field evolves with time. Image sequences taken in the blue continuum, G-band, Ca~\textsc{ii}~K and H$\alpha$ filters were used in this study. It is observed that the suppression found in the chromosphere occupies a relatively larger area confirming previous findings. Also, the suppression is extended to structures directly connected to the magnetic region and is found to get enhanced as the magnetic field strength increased with time. The dependence of the suppression on the magnetic field strength is greater at longer periods and higher formation heights. Furthermore, the dominant periodicity in the chromosphere was found to be anti-correlated with increases in the magnetic field strength.

arXiv commentaccepted for publication in ApJ (in press)

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Cited by in corpus (4)

• Waves in the lower solar atmosphere: the dawn of next-generation solar telescopes
• Magnetoacoustic Wave Energy Dissipation in the Atmosphere of Solar Pores
• An overall view of temperature oscillations in the solar chromosphere with ALMA
• Oscillations In The Line-of-Sight Magnetic Field Strength In A Pore Observed By The GREGOR Infrared Spectrograph (GRIS)