Disappearance or
disruption of a filament
or prominence
observed in ultraviolet
images of the Sun is
used by forecasters as
a CME occurrence
proxy. The NRL 3-D
MHD mesoscale model
examines the
connection between
photospheric magnetic
field evolution on
active region scales
and prominence
evolution. Similarly,
Berkeley/HAO models
suggest the rapidly
evolving, flaring active
regions imaged with
the SOHO MDI
magnetograph are
connected with the
eruption of twisted,
knotted flux tubes from
beneath the
photosphere. The
mesoscale models can
be embedded into the
coronal models to
simulate the reaction of
the corona to active
region-scale magnetic
field evolution,
revealing the
connections between
flares, prominences,
and CMEs.
The top figure suggests
how the evolving
magnetic field looks
around an erupting
prominence, based on
MDI images and a
force-free field model.
The field lines are
superposed on an EUV
image from the EIT on
SOHO. The adjacent
two figures show field
lines from the NRL 3D
mesoscale MHD
models. One snapshot
is of a prospective
evolving prominence
(red), driven by
shearing a multipolar
photospheric field
(blue) along its neutral
line. In the other panel,
active region fields are
shown merging into the
fields of overlying and
adjacent structures.
The lower image is from
HAO/Berkeley MHD
simulations of
kink-unstable flux
tubes rising through
the solar convection
zone and into the
photosphere, where
they manifest
themselves (according
to a Berkeley/NRL
model) as complex
"delta" sunspots like
those associated with
major flares. The
Berkeley/NRL/HAO
modelers will work with
SAIC to introduce key
mesoscale effects into
the global simulations.
Click on the top, bottom and middle right images to view the corresponding
animation. Click on the middle left image to enlarge.
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