1 - Nuclear Sciences and Applications - IAEA

0
FIG. 4.
ONI
O
£
at
o
ID
c
IC
15
#25064 i
10 -
Te(a/2)
—"*
J
xp
\ /
\ /I
\ ^
IAEA-CN-50/A-IV-2 233
/
/
r
i
/
n /
e—^—-~- j
t i
. 1I / - —. 1
/
P
NI
tb
\
= 0.51 MW
i
i
- 1
0.8 1.0 1.2 1.4 1.6 t[s] 18
I
'' 1
/
\
\
f
"''
1 ..—
— •
/**
F?ad(r = 0 )
FIG. 3. ne, ne(0), Te(a/2) and PrJf» as junctions of time.
- 2 -
• ^A X
- I -
:- \
\ \
z
\
V
br
•if
s
1.47 s
/
/
/
/
-
/
in
3 o
i
r
/ rc
/
/
t
1
1 1
0.1 0.2 0.3 rlml O.t "0 0.1 0.2 0.3 rtm] 0.4
Measured Zfe, P^ and PnJne versus minor radius before (a) and after (b) pellet injection.
For the interpretation of the measurements the light impurities C and O are to be
distinguished from copper which - according to spectroscopic measurements - is the
dominating heavy impurity. To explain the central radiation of 300 kW /m 3 at t=1.5 s
we need a Cu concentration of 0.08 % which contributes to Zeff only by about 0.3.
The remaining contribution to {Zeff — 1) can be attributed to 0.7 % oxygen and 2 %
carbon if we assume a ratio of these elements as measured at the boundary. The
peaking factor for these light elements is two between the centre and half the radius,
while theory predicts a ratio of nearly 5.
i
/
j
(b)
/ \
\-
•