Time Distance Study of Isolated Sunspots
نویسندگان
چکیده
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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