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arXiv · 0802.2524

Time Distance Study of Isolated Sunspots

S. Zharkov·C. Nicholas·M. J. Thompson
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Abstract

We present a comparative seismic study of conditions around and beneath isolated sunspots. Using the European Grid of Solar Observations' Solar Feature Catalogue of sunspots derived from SOHO/MDI continuum and magnetogram data, 1996-2005, we identify a set of isolated sunspots by checking that within a Carrington Rotation there were no other spots detected in the vicinity. We then use level-2 tracked MDI Dopplergrams available from SOHO website to investigate wave-speed perturbations of such sunspots using time-distance helioseismology.

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S. Zharkov, C. Nicholas, M. J. Thompson. 2008-02-18. Time Distance Study of Isolated Sunspots. https://doi.org/10.1002/asna.200610744

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