Compact Plasma and Focused Ion Beams

283Electron Plasma Waves Inside Large-Amplitude Electromagnetic Pulses





FeEE

mu

tttvt

ascece

=−

{}

−−() () () ().

(17.1)

The space charge electric eld



E

sc

is determined from Gauss’s law as follows:





∇⋅ ==

−

{}

E

t

t

nt nt e

sc

ie

()

() ()

.

()r

ee

00

(17.2)

Since the dominant mode of propagation of the microwaves (2.45 GHz) in

the cylindrical chamber (R = 6 cm) is TE

11

, the electric eld



Et

a

()

in the cen-

tral region of the plasma chamber and the space charge electric eld



E

sc

are

mainly along radial direction



r

while the propagation vector



k

is along the z

direction. For a probe kept at the center, the electron motion is primarily in

the radial direction, ...