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Ta b l e 3 . 3 The typical specific photon flux of resonant radiation in vapors of alkali metals and the
specific typical flux of the radiation intensity.
I 0 / N 0 ,10 17 Wcm
Vapor
j 0 / N 0 , 100 cm/s
Li(2 2 P )
2.3
6.8
Na(3 2 P 1/2 ) .6
9
Na(3 2 P 3/2 ) .4
5
K(4 2 P 1/2 )
4.5
15
K(4 2 P 3/2 )
3.6
9.4
Rb(5 2 P 1/2 ) .9
0
Rb(5 2 P 1/2 ) .2
.0
Cs(6 2 P 1/2 ) .3
.6
Cs(6 2 P 3/2 ) .7
.6
Figure 3.14 The relative excitation temperature
T
for for resonantly excited atoms versus the
radiation flux according to (3.107).
1.44
j 0 , that is, for alkali metal vapors the number density of reso-
nantly excited atoms exceeds that of ground state atoms by 1.5 times at this photon
flux.
We now consider the character of penetration of the flux of resonant radiation in-
side a plasma. Accounting for the processes of absorption and stimulated emission
for resonant photons, we have the balance equation for the flux j ω ( z ) for resonant
photons propagating in a plasma:
ω
at
j ω D
dj ω
dz D
j ω σ 0 ω N D
j ω σ ω N 0
C
j ω k ω
,
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