The Astrophysical Journal,
Год журнала:
2024,
Номер
975(1), С. 118 - 118
Опубликована: Окт. 29, 2024
Abstract
This
study
investigated
the
mechanisms
of
vorticity
generation
and
role
vortex
tubes
in
plasma
heating
energy
transport.
Vortex
were
identified
using
instantaneous
deviation
technique
MURaM
data
set
a
simulated
solar
plage
region
photosphere.
Within
3D
kinetic
tubes,
misalignment
magnetic
pressure
inverse
density
gradient,
rather
than
baroclinic
effects,
primarily
drive
within
tubes.
During
their
lifetime,
vortices
become
less
dense
as
Lorentz
force
pushes
outwards
against
gradients.
In
upper
photosphere,
contributes
to
adiabatic
cooling
by
expanding
or
compressing
around
turn,
motion
affects
field,
enhancing
current
intensifying
force,
which
may
further
increase
heating.
Moreover,
our
results
confirm
that
can
significantly
boost
viscous
ohmic
on
intergranular
scales
They
generate
more
energy,
with
transport
Poynting
flux
notably
nonuniform
dominant
at
boundaries.
creates
circulation
net
upwards
enhance
chromospheric
support
temperatures.
Space Science Reviews,
Год журнала:
2023,
Номер
219(4)
Опубликована: Май 24, 2023
Abstract
The
term
‘tornado’
has
been
used
in
recent
years
to
describe
several
solar
phenomena,
from
large-scale
eruptive
prominences
small-scale
photospheric
vortices.
It
also
applied
the
generally
stable
quiescent
prominences,
sparking
a
renewed
interest
what
historically
was
called
‘prominence
tornadoes’.
This
paper
carries
out
an
in-depth
review
of
physical
nature
tornadoes’,
where
their
name
subconsciously
makes
us
think
violent
rotational
dynamics.
However,
after
careful
consideration
and
analysis
published
observational
data
theoretical
models,
we
conclude
that
tornadoes’
do
not
differ
any
substantial
way
other
prominences.
There
is
simply
no
unequivocal
evidence
sustained
coherent
movements
would
justify
distinct
category
sharing
with
well-known
atmospheric
phenomenon.
visual
impression
column-like
silhouettes,
perceived
helical
motions,
or
suggestive
Doppler-shift
patterns
all
have
simpler,
more
likely
explanation.
They
are
consequence
projection
effects
combined
presence
oscillations
and/or
counter-streaming
flows.
‘Prominence
thus
just
manifestations
complex
when
observed
specific
projections.
These
coincidental
viewing
angles,
together
fine-structure
dynamics
simple
yet
profoundly
distorting
effects,
may
sometimes
play
havoc
our
intuitive
understanding
shapes
leading
incorrect
analogy
tornadoes.
Astronomy and Astrophysics,
Год журнала:
2023,
Номер
675, С. A94 - A94
Опубликована: Май 17, 2023
Vortex
flows
have
been
found
in
the
photosphere,
chromosphere
and
low
corona
observations
simulations.
It
has
suggested
that
vortices
play
an
important
role
for
channeling
energy
plasma
into
corona,
but
impact
of
vortex
on
not
directly
studied
a
realistic
setup.
We
investigate
coronal
heating
using
high
resolution
simulations
loops.
The
are
artificially
driven,
arise
self-consistently
from
magnetoconvection.
perform
3D
resistive
MHD
with
MURaM
code.
Studying
isolated
loop
Cartesian
geometry
allows
us
to
resolve
structure
interior.
conduct
statistical
analysis
determine
properties
as
function
height
corona.
find
injected
is
generated
by
internal
coherent
motions
within
strong
magnetic
elements.
A
significant
part
resulting
Poynting
flux
channeled
through
tubes
forming
connection
between
photosphere
Vortices
can
form
contiguous
structures
reach
up
heights,
itself
get
deformed
eventually
lose
their
identity
increasing
height.
show
increased
upward
directed
rate
both
effect
becomes
less
pronounced
While
transport
structuring
importance
higher
atmosphere
clear
since
swirls
distinguishable
environment.
reaching
complex
relationship
emission.
Astronomy and Astrophysics,
Год журнала:
2024,
Номер
686, С. A180 - A180
Опубликована: Март 25, 2024
Context.
Flows
are
omnipresent
and
govern
the
dynamics
of
plasma.
Solar
tornadoes
a
class
apparently
rotating
prominences
that
might
be
formed
by
thermal
instability.
In
spectroscopic
studies
on
instability,
background
flow
is
commonly
neglected.
Aims.
We
here
determine
effect
instability
in
cylindrical
magnetic
field
configurations.
How
various
parameters
affect
distribution
eigenmodes
magnetohydrodynamic
(MHD)
spectrum
also
explored.
investigate
whether
discrete
modes
exist.
Methods.
an
analytical
study,
we
extended
upon
literature
including
generic
coordinate
system.
The
non-adiabatic
MHD
equations
linearised,
Fourier-analysed,
examined
to
understand
how
changes
continua.
An
approximate
expression
for
derived
using
Wentzel-Kramers-Brillouin
(WKB)
analysis.
results
then
verified
benchmark
equilibrium
eigenvalue
code
Legolas
.
eigenfunctions
visualised
2D
3D.
Results.
continuum
Doppler-shifted
due
flow,
just
like
slow
Alfvén
Discrete
altered
because
governing
contain
flow-related
terms.
predict
appearance
based
derived.
All
expressions
match
numerical
results.
density
perturbations
not
uniform
or
singular
condensation,
shape
dependence
assumed
waveform
coordinates
wavenumbers.
A
3D
visualisation
total
velocity
shows
helical
heavily
influenced
radial
perturbation.
Conclusions.
analytic
with
them
coronal
equilibrium.
However,
valid
can
applied
other
astrophysical
environments.
Geophysical monograph,
Год журнала:
2024,
Номер
unknown, С. 3 - 38
Опубликована: Апрель 12, 2024
Alfvén
waves
are
propagating
disturbances
of
magnetic
tension
and
one
the
fundamental
in
plasma
at
large
scales.
The
study
solar
corona
has
a
long
continuing
tradition,
started
way
before
were
found
to
be
ever-present
atmosphere.
Their
is
important
for
mainly
two
reasons.
First,
might
play
key
role
long-standing
chromospheric
coronal
heating
problems,
as
well
solar-wind
acceleration
problem,
both
transmitting
energy
photospheric
convection
higher
up
atmosphere
more
directly
means
cascading
dissipating
this
through
various
mechanisms.
Second,
observed
properties
can
used
infer
seismology.
In
review,
an
overview
basic
theoretical
understanding
magnetohydrodynamic
(MHD)
presented,
attempt
clarify
that
greater
class
MHD
encountered
Furthermore,
observational
findings
on
previous
decade
reviewed,
followed
by
short
summary
these
results
still
open
questions.
The Astrophysical Journal,
Год журнала:
2024,
Номер
975(2), С. 176 - 176
Опубликована: Ноя. 1, 2024
Abstract
Magnetic
flux
tubes
in
the
presence
of
background
rotational
flows,
known
as
solar
vortex
tubes,
are
abundant
throughout
atmosphere
and
may
act
conduits
for
MHD
waves
to
transport
magnetic
energy
upper
atmosphere.
We
aim
investigate
Poynting
associated
with
these
within
tubes.
model
a
tube
straight
azimuthal
velocity
component.
The
wave
solutions
equilibrium
configuration
obtained
using
Shooting
Eigensolver
SolAr
Magnetohydrostatic
Equilibria
code
we
derive
an
expression
vertical
component
flux,
S
z
,
modes.
In
addition,
present
2D
visualizations
spatial
structure
different
modes
under
flow
strengths.
show
that
increases
when
compared
no
flow.
When
strength
is
greater
than
100
times
perturbation,
non-axisymmetric
(∣
m
∣
>
0)
by
over
1000%
absence
Furthermore,
fundamental
property
vortices,
namely
they
cannot
solely
produce
upward
untwisted
tube,
meaning
any
observed
must
arise
from
perturbations,
such
waves.
The Astrophysical Journal Supplement Series,
Год журнала:
2023,
Номер
267(2), С. 35 - 35
Опубликована: Авг. 1, 2023
Abstract
Ubiquitous
vortical
structures
are
considered
to
act
as
a
natural
source
of
various
solar
plasma
phenomena,
for
example,
wide
range
magnetohydrodynamic
waves
and
jet
excitations.
This
work
aims
develop
an
advanced
vortex
detection
algorithm
based
on
the
Γ
method
using
separable
convolution
kernel
technique.
is
applied
detect
analyze
photospheric
vortices
in
3D
realistic
magnetoconvection
numerical
observational
data.
We
present
(AGM),
our
results
indicate
that
AGM
performs
with
better
accuracy
comparison
original
method.
The
allows
us
identify
small-
large-scale
no
interposition
without
requiring
changing
threshold.
In
this
way,
nondetection
issue
mostly
prevented.
It
was
found
failed
large
longer-lived
vortices,
which
were
detected
by
AGM.
size
tends
vary
over
time,
most
shrinking
toward
their
end.
vorticity
at
center
also
not
constant,
presenting
sharp
decay
ceases
exist.
Due
its
capability
identifying
minimum
nondetection,
properties—such
lifetime,
geometry,
dynamics—are
captured
than
era
new
high-resolution
observation,
can
be
used
precise
technique
performing
statistical
analysis
atmospheric
vortices.
Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences,
Год журнала:
2020,
Номер
379(2190)
Опубликована: Дек. 21, 2020
This
paper
presents
the
results
of
analysis
three-dimensional
simulations
solar
magneto-convection
that
include
joint
action
ambipolar
diffusion
and
Hall
effect.
Three
simulation
runs
are
compared:
one
including
both
effect;
only
without
any
these
two
effects.
The
magnetic
field
is
amplified
from
initial
to
saturation
level
by
turbulent
local
dynamo.
In
each
cases,
we
study
2
h
simulated
time
after
dynamo
reaches
regime.
We
analyse
power
spectra
vorticity,
fluctuations
different
components
Poynting
flux
responsible
for
transport
vertical
or
horizontal
perturbations.
Our
preliminary
show
produces
a
strong
reduction
vorticity
in
upper
chromospheric
layers
it
dissipates
vortical
perturbations
converting
them
into
thermal
energy.
effect
acts
opposite
way,
strongly
enhancing
vorticity.
When
included,
becomes,
on
average,
more
long-lived
tube-like
structures
produced.
trace
single
structure
its
evolution
pattern
intensification,
their
possible
relation
article
part
Theo
Murphy
meeting
issue
‘High-resolution
wave
dynamics
lower
atmosphere’.