Observational Evidences for Extremely Strong Magnetic Fields in Solar Flares

Vsevolod Gryhorovych Lozitsky

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DOI: 10.4236/ijaa.2011.13019                

Abstract

New observational data related to the X1.1/2N solar flare of 17 July 2004 were investigated and compared with some old data for other powerful flares and non-flare regions. Observations were carried out with the Echelle spectrograph of the Kyiv University Astronomical Observatory. The Stokes I ± V profiles of several metallic lines with different effective Lande factors geff have been analyzed including the FeI 5434.5 line with very low magnetic sensitivity (g_eff = –0.014). The obvious evidences of the emissive Zeeman effect were found as in lines with great and middle Lande factors as in FeI 5434.5 line. On the basis of all analyzed data one can conclude that upper magnetic field limit in flares can reach 70 - 90 kG, i.e. about more order higher than the well-known magnetic fields in great sunspots. The possible physical nature of such superstrong fields is discussed.

Keywords

Sun, Solar Flares, Small-Scale Magnetic Fields, Superstrong Fields

Conflicts of Interest

The authors declare no conflicts of interest.

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