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arXiv · 0910.4247

Variations in $p$-Mode Parameters with Changing Onset-Time of a Large Flare

R. A. Maurya·A. Ambastha·S. C. Tripathy
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Abstract

It is expected that energetic solar flares releasing large amount of energy at the photosphere may be able to excite the acoustic ($p$-) modes of oscillations. We have determined the characteristic properties of mode parameters by applying the ring diagram technique to 3-D power spectra obtained for solar active region NOAA 10486 during the long duration energetic X17.2/4B flare of October 28, 2003. Strong evidence of substantial increase in mode amplitude and systematic variations in sub-surface flows, i.e., meridional and zonal components of velocity, kinetic helicity, vorticity, is found from comparison of the pre- to the post-flare phases.

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R. A. Maurya, A. Ambastha, S. C. Tripathy. 2009-10-22. Variations in $p$-Mode Parameters with Changing Onset-Time of a Large Flare. https://doi.org/10.1088/0004-637x/706/2/l235

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