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arXiv · 1504.03533

Multi-wavelength Fibril Dynamics and Oscillations Above Sunspot - I. Morphological Signature

Abstract

In this work we selected one particular fibril from a high resolution solar chromosphere observation from the Dutch Open Telescope, and tried to obtain a broad picture of the intricate mechanism that might be incorporated in the multiple layer of the Solar atmosphere in high cadence multi-wavelength observation. We analyzed the changingvfibril patter using multi-wavelength tomography, which consists of both H$\alpha$ line center \& the blue wing, Doppler-signal, Ca II H, and the G-band. We have found that the intermittent ejected material through fibril from Doppler images has clearly shown oscillation mode, as seen in the H$\alpha$ blue wing. The oscillations in the umbrae and penumbrae magnetic field lines that are above the sunspot cause a broadening and forms the area like a ring shape from 3 to 15-minute oscillations as function of height. These made a distinct boundary of umbrae and penumbrae which suggest the comb structure, and indicate that the oscillations could propagate along the inclined magnetic flux tubes from below. The 3-minute strongly appeared in the broadly inclined penumbrae magnetic filed lines and gave the clear light-bridge. The well known 5-minute was dominated in the umbrae-penumbrae region boundary, the long 7-minute one was transparent in the H$\alpha$ blue wing, but this was the same with 10 and 15-minute, it was concentrated in the inner-penumbrae, as seen in the H$\alpha$ line center. From these findings we propose a picture on the role of fibril as the fabric of interaction between the layers, also the related activites around the active region under investigation.

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Emanuel Sungging Mumpuni, Dhani Herdiwijaya, Mitra Djamal, Thomas Djamaluddin. 2015-04-14. Multi-wavelength Fibril Dynamics and Oscillations Above Sunspot - I. Morphological Signature. https://doi.org/10.1088/1674-4527%2F15%2F11%2F007

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