Alcator C-Mod Weekly Highlights
			Dec. 19, 2005

FY2006 weeks of research operations:
   Planned: 12 weeks (tentative)
   Completed: 4 weeks

Operations
----------

Scheduled maintenance activities continued at Alcator C-Mod last week. No
plasma operations were scheduled.

The tokamak has been warmed up in preparation for a clean vent to re-install
the Lower Hybrid launcher. The machine was leak checked and a small leak at a
beryllium window at B-port was identified.

The maintenance period is scheduled to continue this week. Access to the cell
and power room may be restricted on some days due to high power testing and
calibration of the Lower Hybrid system.

Physics
-------

Ron Bravenec (UT-FRC) completed a linear GS2 analysis of a C-Mod shot to
determine critical gradients for ETG and ITG/TEM modes. This work is intended
to provide a tool for analysis of data from MP#443 "Temperature scale length
measurements using Btor sweeps".

ICRF System
-----------

Transmitter FMIT#4 has been reassembled following preventive maintenance. New
ferrite material has been installed, and finger stock and end stops were
replaced on the screen grid slide coupling. Standard cleaning of the anode
cooling tubes and insulator surfaces was also completed.

Resistors in the crowbar cabinets for transmitters FMIT#3 and 4 were
replaced. A vacion pump on FMIT#2 was repaired and returned to service.

Diagnostic Neutral Beam Systems
-------------------------------

The beam was operated into gas in the C-Mod chamber on Thursday in support of
beam width measurements.

The calorimeter amplifier, along with the cabling that connects it to CAMAC
digitizers,  has been repaired and re-installed in the beam rack. A faulted
ion gauge controller in the DNB vacuum monitoring system was replaced with a
spare from the vacuum shop.

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

Preliminary drive leg calibrations were completed, allowing high power testing
of the forward and rear waveguide assembly to begin. High power calibrations
at 10-80kW (in 10kW increments) were completed for both carts 1 and 2. High
power calibrations on the third cart will begin this week.

We have found hairline cracks in the outer-most waveguide windows of
the Lower Hybrid couplers that could eventually result in vacuum
leaks. These guides are being blanked off to eliminate the possibility
of leaks developing during C-Mod operation. Simulation of the modified
configuration indicates very little impact on the launched spectrum.
modifications.

Travel and Visitors
-------------------

Ron Bravenec (UT-FRC) completed a two-week visit to C-Mod. In addition to
working on GS2 analysis of C-Mod data (see above), he conducted tests of
monitors for the DNB and rearranged the BES fibers for broadband fluctuation
measurements.

Bob Granetz attended the first day of the NSTX research forum and presented
a talk on near-term C-Mod research plans, upgrades, and opportunities for
C-Mod/NSTX collaborative research.  Amanda Hubbard presented an ITPA
collaboration proposal to the NSTX forum, using remote video-conferencing
tools.

Mark May from LLNL visited C-Mod last week to configure the new CCD camera
used on the LLNL Doppler Spectrometer. He also discussed with Alex Graf
(University of California), Jim Terry and Bruce Lipschultz future experiments
with the Doppler Spectrometer.

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