Oscillations and running waves observed in sunspots ? II . Photospheric waves
نویسندگان
چکیده
To continue our study of waves related to sunspots in the photosphere, we analyzed CCD, high resolution sunspot observations obtained in the Fe i 557.6 nm line. We produced " time slice images " which reveal inward slow propagating waves in the photospheric penumbra and outward propagating waves in the area around the sunspot. The phase velocity of the waves is near 0.5 km s −1 in both cases and their horizontal wavelength about 2500 km. The waves could be related either to solar p-modes or to the subphotospheric layer large-scale convection.
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تاریخ انتشار 2000