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Initial results from SECIS observations of the 2001 eclipse

A. C. Katsiyannis·D. R. Williams·F. Murtagh·R. T. J. McAteer·F. P. Keenan
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Abstract

SECIS observations of the June 2001 total solar eclipse were taken using an Fe {\sc xiv} 5303 Å filter. Automated tools based on wavelet analysis was used to detect intensity oscillations on various areas of the images. Statistical analysis of the detections found in the areas covered by the moon and the upper corona allowed us to estimate the atmospheric and instrumental effects on the detection of intensity oscillations. An area of the lower corona, close to Active Region 9513, was found with a statistically significant amount of intensity oscillations with periodicity of $\sim7.5s$. The shape of the wavelet transformation of those detections matches theoretical predictions of sausage-mode perturbations and for the first time in the SECIS project, second order oscillations were also detected.

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A. C. Katsiyannis, D. R. Williams, F. Murtagh, R. T. J. McAteer, F. P. Keenan. 2004-11-26. Initial results from SECIS observations of the 2001 eclipse. https://arxiv.org/abs/astro-ph/0411722

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