Vadim M. Uritsky, Joseph M. Davila
Multiscale topological complexity of solar magnetic field is among the
primary factors controlling energy release in the corona, including associated
processes in the photospheric and chromospheric boundaries. We present a new
approach for analyzing multiscale behavior of the photospheric magnetic flux
underlying this dynamics as depicted by a sequence of high-resolution solar
magnetograms. The approach involves two basic processing steps: (1)
identification of timing and location of magnetic flux origin and demise events
(as defined by DeForest et al., 2007) by tracking spatiotemporal evolution of
unipolar and bipolar photospheric regions, and (2) analysis of collective
behavior of the detected magnetic events using a generalized version of
Grassberger - Procaccia correlation integral algorithm. The scale-free nature
of the developed algorithms makes it possible to characterize the dynamics of
the photospheric network across a wide range of distances and relaxation times.
Three types of photospheric conditions are considered to test the method: a
quiet photosphere, a solar active region (NOAA 10365) in a quiescent
non-flaring state, and the same active region during a period of M-class
flares. The results obtained show (1) the presence of a topologically complex
asymmetrically fragmented magnetic network in the quiet photosphere driven by
meso- and supergranulation, (2) the formation of non-potential magnetic
structures with complex polarity separation lines inside the active region, and
(3) statistical signatures of canceling bipolar magnetic structures coinciding
with flaring activity in the active region. Each of these effects can represent
an unstable magnetic configuration acting as an energy source for coronal
dissipation and heating.
View original:
http://arxiv.org/abs/1111.5053
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