Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, no. 55, p. 51-56 (2017)
Magnetic fields in proton solar flare of X17.2/4B class according to data of simultaneous measurements in a few spectral lines
V. Lozitsky, Dr. Sci.,
N. Lozitska, Ph. D.,
Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv
Abstract
Spectral-polarized magnetic field measurements in solar flare of 28 October 2003 of Х17.2/4B class are compared in six FeI lines and in Нα line. Observations were carried out on Echelle spectrograph of horizontal solar telescope of Astronomical Observatory of Taras Shevchenko National University of Kyiv. Presented data relate to peak phase of flare and a place of photosphere outside sunspots where effective (average) magnetic field in FeI 6302.5 line was about 100 G and had S polarity. Measured splitting of emissive peaks in cores of strong FeI lines of 15th multiplet correspond to stronger fields, in range 550–700 G and S polarity too. Noticeablre splitting of emissive peaks (11–20 mÅ) were found also in Fe I 5434.527 line with effective Lande factor geff = –0.014. Value of this splitting and its sign indicate the existence of extremely strong fields of 25–50 kG of opposite (N) polarity which had negative Doppler velocities (lifting of plasma) on level of 1.7–2.2 km/sec. Magnetic field according to Нα line was 300 G and N polarity. Presented results indicate the essential inhomogeneity of magnetic field in flare volume which include the opposite polarities along the line of sight and wide range of effective magnetic fields.
Key words
Sun, solar magnetic fields, solar flares, proton flare of X17.2/4B class, Echelle Zeeman spectrograms, splitting of emissive peaks, magnetic field strengths in photosphere, temperature minimum zone and chromosphere
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