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arXiv · 1304.5805

On the Seismicity of September 7, 2011 X1.8-class Flare

S. Zharkov·L. M. Green·S. A. Matthews·V. V. Zharkova
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Abstract

We present results of our preliminary analysis of acoustically active X-class flare of September 7, 2011. We report two acoustic sources detected via acoustic holography and verified by finding a ridge in time-distance diagrams. We compare the directional information extracted from time-distance and acoustic holography, showing a good agreement in this case. We report that the direction where amplitude of the wave-front is the largest lies through the strong magnetic field and sunspot, suggesting that absorption of the acoustic wave power by magnetic field can be ruled out as a wave anisotropy mechanism in this case.

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S. Zharkov, L. M. Green, S. A. Matthews, V. V. Zharkova. 2013-04-21. On the Seismicity of September 7, 2011 X1.8-class Flare. https://doi.org/10.1088/1742-6596%2F440%2F1%2F012046

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