IPP Annual Report 2007 - Max-Planck-Institut für Plasmaphysik ...

of λ/Δλ≈6800 is reached despite the compact dimensions.
First results were obtained during the 2007 campaign allowing
the extraction of Ar concentrations and ion temperatures
in the central plasma with a temporal resolution of 8 ms.
Dust Measurement
The production of dust is an important safety issue for ITER.
Investigations in AUG have been started to compare different
dust measurement techniques and to quantify the dust produced
in a tungsten wall device. Methods under test include a filtered
vacuum collection technique, Si wafer collectors, an in-situ
monitor developed by PPPL and a fast visible camera with a
tangential view. First investigations show spheres of tungsten
with a typical diameter of 1 μm. With a frame rate of 20 kHz,
the fast camera can produced 8 GB of data during one discharge.
Up to now only manual data evaluation has been done.
Typical speeds of 100 m/s are observed for dust particles.
ITER Core Charge Exchange System
Simultaneous observations of charge exchange (CX) transitions
from Ar XVI, XVII and XVIII were obtained in AUG
H-mode plasmas to provide experimental validation of new
fundamental CX cross-sections for Ar. In addition, the influence
of W I and W II line intensities on ITER CX spectra
has been calculated. Using a simple model for W sources, it
is calculated that the CX-lines from C VI and N VII are
unperturbed while the Be IV and He II spectrum has to deal
with only two W I lines. The Ne X and Ar XVIII CX-lines
suffer from several W I lines and therefore may not be suitable
for ion temperature measurements, unless the lines of
sight are chosen with great care.
ITER Design Review
Operating Scenarios for ITER (Current Rise and Current Decay)
In order to achieve the range of scenarios foreseen for ITER,
it is necessary to access a range of q-profiles at the start of the
burn phase. For the ITER Design Review, experimental data
from ASDEX Upgrade have been supplied for two cases.
The first case is based on a dataset of 84 Ohmic pulses with
q 95