Results of the investigation of fast magnetic field oscillations in a sunspot on the basis of simultaneous measurements in the Kyiv and Crimea observatories

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Astronomy and Astrophysics
1Lozitska, NI, 2Malashchuk, VM, 2Stepanian, NN
1Astronomical Observatory of the Taras Shevchenko National University of Kyiv,Kyiv, Ukraine
2Scientific-Research Institute “Crimean Astrophysical Observatory” of the Ministry for Education and Science of Ukraine, Nauchny, AR Crimea, Ukraine
Kosm. nauka tehnol. 2007, 13 ;(Supplement1):101-104
https://doi.org/10.15407/knit2007.01s.101
Publication Language: Russian
Abstract: 
Fast oscillations of sunspot magnetic fields were studied using visual measurements of the Zeeman splitting in the Fe I 525.02 and Fe I 630.25 lines observed in umbra of the largest sunspot of the active region NOAA 10953. During 27–28 April 2007, about 600 measurements were carried out with solar telescopes of the Kyiv and Crimea observatories including 112 quasi-simultaneous measurements (with a time gap less than 1 min). Reducing the observational data with the use of wavelet, Fourier and autocorrelation analysis showed the existence of 6–7 min and 14–16 min oscillations; their amplitudes were 2±1 cT and 3±1 cT, respectively.
Keywords: amplitudes, analysis, observational data, oscillations
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