1 - Nuclear Sciences and Applications - IAEA

232 KAUFMANN et a\.
16
12
o 8
. At = 17 ms
# 25 064
(a)
°0 0.1 0.2 0.3 r[ml O.t
16
12
? 8
At = 17 ms
(b)
0 0.1 0.2 0.3 r[m] 0A
FIG. 2. ne versus r: (a) measured; (b) calculated.
to rise drastically. During the fully developed accumulation period [t > 1.6 s) it is
enhanced by a factor of ~ 20 compared to the initial phase. In figures 4a and 4b
we show the radial profiles of Zc/f and the bolometrically determined radiation losses
at two different times ta and tb (see fig. 3). The Ze/f profile is flat before (ta) and
slightly peaked during the accumulation phase after pellet injection (tb). For check
of consistency, 2ff[i) derived from loop voltage, current and temperature profiles,
and assuming neoclassical theory, was compared with a temperature weighted 2^j
from bremsstrahlung profiles. The values agree by more than 20 %. The impurity
accumulation is clearly demonstrated by the peakedness of the normalized bolometric
radiation profile Prad/ne shown in fig. 4b.