Alcator C-Mod Weekly Highlights
			Jan 17, 2006

FY2006 weeks of research operations:
   Planned: 14 weeks
   Completed: 4 weeks

Operations
----------

We continued preparations for the next run period with calibration of
critical instrumentation amplifiers and optical links.  General
maintenance of the alternator support facilities continued. Liquid
nitrogen cooling and heater systems are being prepared for operation.

Upgrades of C-Mod engineering system PLC to PC interface software
continued last week.


Physics
-------

For future tokamak reactors, there is concern that without the
momentum input from neutral beam injection, the beneficiary effects of
plasma rotation (H-mode transition, ITB formation, RWM stabilization)
will be absent. John Rice has been investigating the spontaneous
rotation observed on many devices without external momentum input
which may provide the solution to this problem. In order for the level
of spontaneous rotation in ITER to be predicted, a scaling derived
from the existing database is desired. From a comparison of
observations of spontaneous rotation seen on many devices (C-Mod, JET,
Tore Supra, DIII-D and JT-60U), induced with a variety of different
methods (ICRF, ECH, LH and Ohmic), it has been found that there is a
good correlation between Mach number and betaN.

The Alcator Beowulf linux cluster (Unity) was upgraded from a
relatively old customized version of linux to the latest release of
Red Hat Enterprise Linux 4. The master node and the 35 diskless slave
nodes are now running this standard version of the operating system.


Lower Hybrid System
-------------------

Installation of the four stainless steel couplers onto the forward
wave guide was successfully completed last week. After the aluminum rf
gaskets were annealed they compressed to the design specification and
allowed metal-to-metal contact of the coupler and launcher flanges.
Installation of thermocouples and Langmuir probes on the launcher
proceeded over the weekend.  The launcher has now been installed on
C-Mod.

Work continued on the documentation and analysis of the phase and
amplitude calibration data.  Modifications to spreadsheet information
and database nodes have been made.


ICRF Systems
------------

Maintenance of the FMIT transmitters and transmission line components
and preparations for operation continued last week.


Diagnostics
-----------

Work continued on the interlock system needed to protect the inner
wall from the long pulse diagnostic neutral beam.  This system takes
input from several diagnostics including the interferometer, IR
optical pyrometer, visible light, and magnetics.


Travel and Visits
-----------------

Joe Snipes was at JET last week working on the MIT/JET/CRPP
collaboration on Alfven Eigenmodes and Energetic Particle Wave
Interactions.  He also had discussions with the MAST group on their
new TAE antennas planned for installation in the summer.
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