Multifractal analysis based on the Choquet capacity: Application to solar magnetograms

• Published in: Physica A 2012-09, Vol.391 (18), p.4290-4301
• Main Authors: Makarenko, N.G., Karimova, L.M., Kozelov, B.V., Novak, M.M.
• Format: Article
• Language: English
• Subjects: Discs; Doppler; Doppler effect; Magnetic properties; Multifractal formalism; Solar magnetic field; Spectra; Sun; The Choquet capacity
• ISSN: 0378-4371; 1873-2119
• DOI: 10.1016/j.physa.2012.03.042

We explore the multiscale properties of the line-of-sight component of Solar magnetic fields using magnetograms of the full disc obtained from the Michelson Doppler Imager (MDI) on board the Solar and Heliospheric Observatory (SOHO). Multifractal spectra are estimated by different methods, based on the Choquet capacity, instead of the traditional Borel measure. We have extracted spectra corresponding to active regions (AR) as well as those from quiet regions of the Sun. The shapes of spectra of active regions and those of quiet regions of the Sun are different, displaying different lengths of left-hand and right-hand branches. We indicate that multifractal scaling of magnetograms can be produced by a set of statistically similar elements in digital high resolution images. The same features are found in images of many terrestrial scenes. ► We explore multiscale properties of solar magnetograms. ► The Choquet capacity is used to calculate spectra of various solar regions. ► We provide a technique to determine robust estimation of multifractal spectra. ► In addition to turbulence, other mechanisms give rise to multifractal spectra.