3D Simulations of Large-Scale Coronal Dynamics
Judy Karpen
Understanding the origins of solar activity is one of the primary
science objectives of Solar B. Although great strides have been made
during the past decade toward a comprehensive picture of coronal mass
ejections (CMEs) and flares, we still do not fully understand one of
the most fundamental aspects: the evolution of filament channels, the
highly sheared magnetic fields that produce large-scale eruptions on
the Sun. A multi-faceted approach is required to tackle this crucial
problem, involving coordinated observations, analytic theory, and
computational studies. Both observing and modelling coronal eruptions
are particularly challenging, due to the enormous range of relevant
spatial scales. Energy storage and dynamics affect structures as large
as transequatorial loops, while the release process probably occurs on
the miniscule scales of current sheets and nulls.
The NRL Solar Theory group has been using theory and numerical
simulations to understand the complete process: the development of
filament-channel magnetic structure (sheared-arcade model), the dynamic
generation of condensations constituting a prominence within this
structure (thermal nonequilibrium model), and the explosive onset of
CMEs and associated flares (breakout model). Thanks to recent hardware
and software advances, we can now critically evaluate theories of
filament-channel evolution, prominence formation, and CME initiation,
and predict key signatures for comparison with observations. I will
summarize the results of our simulations and their implications for
filament-channel evolution and eruption. I will also discuss how the
powerful combination of high-resolution/large FOV instruments on Solar
B, complemented by overlapping STEREO coverage, will be essential for
detecting specific observable signatures predicted by these models,
from detecting reconnection-driven flows to deciphering the 3D magnetic
structure of prominences and CMEs.
Correspondence
Judy Karpen (judy.karpen@nrl.navy.mil), NRL
presentation
invited