Multipactor in Low Pressure Gas and in ... - of Richard Udiljak

upper right region of the figures, where the electron growth is very slow.
There is good agreement in the general behaviour and the transition
from double-sided to single-sided multipactor occurs at more or less the
same impedances for the different zones in both the PIC-simulation and
the theoretical data, since the non-zero initial velocity in the PIC-data
is small relative to the oscillatory velocity.
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0.2 0.4 0.6 0.8 1 1.2 1.4 1.6
Z/Z (Z =50 Ω)
0 0
Figure 5.8: Number of electrons after 200 RF-cycles. The white dots are
points of 2-sided multipactor, the green and yellow dots 1-sided
multipactor, and the white dashed lines correspond to Ri,min =
Ro/ √ 2 (left) and Ri,min = Ro/ √ 3 (right) - all from Fig. 5.7.
Parameters used: σse,max = 1.6, W1 = 50 eV, vT/vmax = 0.01,
ρ = Vω,o/vmax = 0.5, and f = 1.5 GHz.
The straight lines on the right hand side of Fig. 5.8 reveal that this
should be single-sided multipactor. This is confirmed by looking at the
ratio of power deposited on the inner and the outer conductors, which
directly identifies the type of discharge. In Fig. 5.9, the dark blue areas
are regions where most or all power is deposited on the outer conductor,
which implies single-sided multipactor on this conductor. The orange
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