Newsgroups: sci.physics.plasma
From IRBY@CMOD2.PFC.MIT.EDU Tue Jun 18 20:09:08 1996
From: IRBY@CMOD2.PFC.MIT.EDU
Organization: MIT
Subject: Alcator C-MOD Weekly Highlights

Alcator C-MOD Weekly Highlights
June 18, 1996

We have begun re-installation of the outer divertor modules.
This process will continue for approximately the next ten days. Five
out of ten modules are now installed. Invessel work associated with
diagnostic upgrades is now determining the module installation schedule.
Work on other invessel systems continues. The strain gauges have been
installed on the inner vessel wall, and the associated cables are being
run. The diborane feed tubes have been machined and welded, and clamps for
holding it to the vessel are being machined. Clamps for the glow
discharge coax feeds are complete. A prototype glow discharge insulator
was hi-potted successfully. The remaining insulators will be in-house
by the end of the week.
Stress cones have been installed on all 13.8 kV AC and high voltage
DC connections associated with the new transmitters. Upgraded transformers
have been installed in the driver cabinets.
The new TF upper arm cooling valves have been tested and are
operational through the PLC. The new Paragon screen is complete and
tested. The cryo valve box and LN2 lines are being insulated and
sealed in preparation for the GN2 purge.
Work on the edge Thomson scattering continues both at MIT and
PPPL. Analog fiber links have been installed between the laser room and
cell. The D to A module for the HeNe dither drive was tested,
but a failed HeNe power supply kept a system test from occurring. The YAG beam
enclosure is nearly complete, as is alignment of the polychromator. The
signal fibers are mounted and ready to be mated to the polychromator. An
invessel inspection of the fibers was done to confirm their orientation in
their holder. A permanent protective housing for these fibers is under
construction.
TORVAC control modifications for the new forepump are complete
and the PLC/Paragon software is being updated. The new pump will allow
one pumping stack to operate independently of the other. This change is
needed to provide better differential pumping for the RGA and to allow
higher throughput for boronization.
Analysis of data from the last run campaign continues. Central
impurity toroidal rotation during ohmic discharges has been
measured from the doppler shifts of x-ray emission lines. The magnitude
of the rotation is a few x 10^4 m/s, in the direction opposite to the
plasma current, and is in qualitative agreement with the predictions of
neo-classical theory.
Earl Marmar was at PPPL last week attending the FESAC Scientific
Issues Subcommittee (SciCom) meeting.