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A
Projection of magnetic field lines onto the plane centered z=94.8 cm
from the targets. The data were derived from vector magnetic field
measurements taken on five planes at distances ranging from 31.5 to 284.4 cm
from the targets. The time is 5.25 microseconds after the targets are struck. Magnetic
field data in each plane were acquired at 900 spatial locations on a rectangular grid with 1 cm spacing in the x and y directions.
The background magnetic field which goes out of the plane of the figure is not included.
The field lines are colored according to the local magnetic field in G.
Two reconnection regions are visible above and below the central current channel.

See papers related to this image:

Three-dimensional current systems generated by plasmas colliding in a background magnetoplasma.

A field line bundle composed of those field lines that pass near the upper reconnection region shown in Figure 8.

The color bar is the same as that in Figure 8.
The background magnetic field is in the z direction but is not included in this bundle.
(a) is a global view looking away from the cathode plasma source.
To help grasp the three-dimensional nature of the image, a semitransparent plane with white grid lines on a black surface is placed at z=95cm.
Because of the transparency, field lines appear grayed if they are beneath the grid lines and are darker beneath the open areas.
Field lines above the plane are unaffected.
The gray grid lines are spaced at 5 cm intervals and are centered at z = 95 cm.
Data were acquired at 1 cm intervals everywhere in the transverse plane.
Note in (b) that the field lines span both sides of the grid, and near the reconnection point have a substantial out-of-plane component.

See papers related to this image:

Three-dimensional current systems generated by plasmas colliding in a background magnetoplasma.

A
three-dimensional view of the instantaneous magnitude of the
magnetic field of an Alfvén wave, measured in the LArge
Plasma Device. The wave propagates primarily in the direction
of the ambient magnetic field, but there is also cross-field
propagation of wave energy until the wave reaches the radial
boundary of the plasma. Alfvén waves with small cross-field
structure, such as the one visualized in this image have electric
fields parallel to the background field and therefore can
accelerate electrons. This mechanism is thought to play a
key role in the formation of the earths aurora [See
Wygant, et al., JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 105,
NO. A8, doi:10.1029/1999JA900500, 2000]


See
papers related to this image:

http://plasma.physics.ucla.edu/bapsf/papers/IEEE_cyclotron_waves.pdf

http://plasma.physics.ucla.edu/bapsf/papers/Vincena_PRL_2004.pdf

Contact: vincena@physics.ucla.edu
for more information.






Whistler
waves are launched from a small loop antenna which then propagate
into a carefully created density striation (field-aligned,
cylindrical depletion in plasma density.) The waves undergo
a linear conversion to lower hybrid waves with a much shorter
perpendicular wavenumber but with a large electric field which
can then heat the plasma ions. Using carefully scaled dimensionless
parameters, this experiment recreates the essential physics
of a process which occurs in the earths ionosphere.


See
papers related to this image:

http://plasma.physics.ucla.edu/bapsf/papers/Bamber_jgr.pdf







The
instantaneous vector wave magnetic field produced by two interacting
Alfvén waves. The wave propagates from left to right
and the relative phase of the two waves is such that they
constructively interfere at the center of the plasma column,
producing a perturbation of delta-B/B = 10^-3.


See
papers related to this
image:

http://plasma.physics.ucla.edu/bapsf/papers/Budapest_paper.pdf






This
is a snapshot of the time-varying magnetic field measured
in a plane perpendicular to the background magnetic field
within the plasma of LAPD. In this experiment, high-power
microwaves are directed from outside of the chamber, through
a window, and into the plasma. The microwaves are incident
from y=0 and x=-50cm. They heat the plasma in a narrow region
at the edge (x=-20cm) producing a field-aligned burst of electrons
(a current channel) which shows up as a circulation of the
magnetic field vectors.