The Morphologic Properties of Magnetic networks over the Solar Cycle 23

TL;DR

This study analyzes the morphological properties of solar magnetic networks over Solar Cycle 23, revealing their fractal nature, size variations with latitude, and anti-correlation with sunspot activity, using magnetogram data and watershed algorithms.

Contribution

It provides new insights into the fractal characteristics and latitudinal variations of solar magnetic networks during Solar Cycle 23.

Findings

Magnetic cell areas are smaller at lower latitudes.

Magnetic networks exhibit fractal properties with D_f ≈ 1.253.

Fractal dimension and network size are anti-correlated with sunspot area.

Abstract

The morphologic properties of the magnetic networks during Carrington Rotations (CR) 1955 to 2091 (from 1999 to 2010) have been analyzed by applying the watershed algorithm to magnetograms observed by the Michelson Doppler Interferometer (MDI) on board the Solar and Heliospheric Observatory (SOHO) spacecraft. We find that the average area of magnetic cells on the solar surface at lower latitudes (within +-50 degree) are smaller than those at higher latitudes (beyond +-50 degree). Statistical analysis of these data indicates that the magnetic networks are of fractal in nature, and the average fractal dimension is D_f = 1.253+-0.011. We also find that both the fractal dimension and the size of the magnetic networks are anti-correlated with the sunspot area. This is perhaps because a strong magnetic field can suppress spatially modulated oscillation, compress the boundaries of network cells, leading to smoother cell boundaries. The fractal dimension of the cell deviates that predicted from an isobar of Kolmogorov homogeneous turbulence.