On sunspot penumbra oscillation

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Astronomy and Astrophysics
1Gopasyuk, OS, 1Gopasyuk, SI
1Crimean Astrophysical Observatory, Ministry for Education and Science of Ukraine, Nauchnyj, Crimea, Ukraine
Kosm. nauka tehnol. 2004, 10 ;(5-6):135-137
https://doi.org/10.15407/knit2004.05.135
Publication Language: Russian
Abstract: 
Oscillations of the penumbrae of four sunspots are investigated from the observations of longitudinal components of the magnetic field and velocity in the photospheric line Fel 525.3 nm. The period of oscillations of sunspot penumbrae lies in the range from 3.4 to 7.7 days. The phase of the azimuthal component of the velocity was ahead of the phases of all other components. If the density of plasma in a penumbra is 10 sup {-4} kg/m3(the same as in the photosphere), the magnetic energy of oscillations exceeds the kinetic energy of the same components by a factor of 10 to 100.
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