| P. A. Conlon, P. T.Gallagher, R. T. J. McAteer, J. Ireland, C. A. Young, P. Kestener, R. J. Hewett, K. Maguire |
Magnetohydrodynamic turbulence is thought to be responsible for producing complex, multiscale field distributions in solar active regions. Here we explore the multiscale
properties of a number of evolving active regions using magnetograms from the Michelson
Doppler Imager (MDI) on the Solar and Heliospheric Observatory (SOHO). The multifrac-
tal spectrum was obtained using a modified box-counting method to study the relationship
between magnetic field multifractality and region evolution and activity. The initial emer-
gence of each active region was found to be accompanied by characteristic changes in the
multfractal spectrum. Specifically, the range of multifractal structures (Ddiv ) was found
to increase during emergence, as was their significance or support (Cdev ). Following this, a
decrease in the range in multfractal structures occurred as the regions evolved to become
large-scale, coherent structures. From the small sample considered, evidence was found for
a direct relationship between the multifractal properties of the flaring regions and their
flaring rate.
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