From: IRBY@CMOD.PFC.MIT.EDU
Subject: Alcator C-MOD Weekly Highlights
Newsgroups: sci.physics.plasma
Organization: MIT


Alcator C-MOD Weekly Highlights
April 1, 1997


Even with a major blizzard causing a slowdown in work, good
progress was made in C-Mod reassembly. We have completed all
magnet bus installations and the associated inspections, hi-pots, and
ringing tests. All magnet cooling lines have been installed and verified
for proper operation. The cryostat has been completed and sealed. The middle
tier igloo blocks have been installed, and diagnostics requiring support
from the igloo are now being brought back on line. Upper and lower
crosses have been installed, and periscopes, probes, magnetics
and MHD connectors, divertor thermocouples, and glow discharge feedthroughs
and coaxes, which attach to the crosses, have been re-installed. Invessel
alignments and calibrations continue. New shutters to protect optical
components from the effects of boronization have been installed.
Installation of power supplies for the off-line shakedown of the
diagnostic neutral beam is well underway. Work continued on the design of
controls for the new ACCEL supply and the associated crowbar circuit. The
arc/filament/snubber supply was filled with filtered, degassed oil, and
should soon be ready for further tests. Work on the magnet power supplies
and new rf transmitters also continues. We are now bringing the TMX supplies,
which power our EF2 and EFC magnets, back into operation. The control
system for the new rf transmitters has successfully controlled the new tuners.
We continue to make plans for in cell installations of rf components including
coax runs and dc breaks.
There was significant progress in the development of the DNB
CXRS and MSE diagnostic systems. Since the CXRS optics are in the final
design stage by UT-FRC, a meeting was held to ensure that all of the needs
of the C-Mod experimental program would be met. The initial results of a
feasibility study of MSE at PPPL was received and looks very promising.
The vacuum interface for the UT-FRC Langmuir probe was successfully
installed. This probe is optimized for edge turbulence measurements, and
assembly of the probe itself is now being completed at the University of
Texas.
C-Mod has now contributed five shots to the ITER profile database.
These shots included examples of ELM free H-modes, ELMy/EDA H-modes, reversed
field L-modes (so called enhanced L-modes) and a normal L-modes.
The new thermoelectric coolers for stabilizing the reflectometer
Gunn diodes arrived at MIT from PPPL this week. Mike McCarthy from PPPL
designed this system. Integration of the coolers into the reflectometer
redesign has begun.
Dr. N. Ohno (Nagoya Univ.) is visiting the PSFC Divertor Theory Group
as a part of the US-Japan collaboration. Dr. Ohno, with PSFC scientists, will
be analyzing data from the NAGDIS-II divertor simulator (Nagoya Univ.)
for evidence of Molecular Activated Recombination. Jim Weaver and Ben
Welch from the University of Maryland are visiting to help install there
diagnostics on C-Mod and begin calibrations. Mark May and Vlad
Soukhanovskii are here from JHU to complete installation of their divertor
spectrometer. Joe Bartolick, Boris Grek, and Dave Johnson from PPPL are
here to finish installation and alignment of the X-Point Thomson scattering
system.
Miklos Porkolab attended the Office of Fusion Energy Sciences
lab director's meeting in Washington, DC.