Prasad, S.K., Jess, D.B., Jain, R. orcid.org/0000-0002-0080-5445 et al. (1 more author) (2016) Time-dependent suppression of oscillatory power in evolving solar magnetic fields. Astrophysical Journal, 823 (1). 45. ISSN 0004-637X
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 power maps, 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 utilizing 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 ii K, and Hα 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.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 The American Astronomical Society. This is an author produced version of a paper subsequently published in Astrophysical Journal. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | Sun: chromosphere; Sun: evolution; Sun: magnetic fields; Sun: oscillations; Sun: photosphere |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 13 Jul 2016 14:34 |
Last Modified: | 01 Nov 2016 21:14 |
Published Version: | http://dx.doi.org/10.3847/0004-637X/823/1/45 |
Status: | Published |
Publisher: | American Astronomical Society |
Refereed: | Yes |
Identification Number: | 10.3847/0004-637X/823/1/45 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:102263 |