/                   Alcator C-Mod Weekly Highlights
                          September 13, 2004


FY 2004 weeks of operation planned: 18 weeks, completed: 18.9 weeks.

We are currently up-to-air with the primary goal of installing the
lower hybrid launcher.  In addition, a large number of in-vessel
activities are ongoing in support of ICRF and diagnostic systems.
Maintenance and upgrades to diagnostic and power systems are also in
progress.


Physics
-------

Kirill Zhurovich and Darin Ernst have developed a set of fitting
routines to combine visible bremsstrahlung, edge and core Thomson
scattering, and ECE data into a consistent set of density and
temperature profiles.  These profiles should be very useful as input
to TRANSP.  User friendly driver routines and population of our
MDSplus database with this profile information are being considered.


Operations
----------

During the next campaign twelve molybdenum tiles in the C-Mod outer
divertor will be replaced with W-brush tiles, whose design was
developed at MIT with consultation from Sandia National Lab,
Albuquerque.  They are prototype tiles in a program aimed at
optimization of the plasma-facing components for long-pulse, high
power, AT studies on C-Mod. The operational experience gained with the
W material and the brush design will be in direct support of
preparations for ITER.  Two columns of four tiles each will be at
leading edge locations, and one column will be near the middle of the
divertor module with moly tiles on either side.  W-brush tiles at all
locations are being carefully machined to the shape of the Mo tiles
they are replacing. The tiles will be monitored with a number of
diagnostics.  Three W-brush tiles and some W rods have been sent to
Sandia for high heat load testing expected to be completed by the end
of August.

We continued general maintenance of the MIT Alternator last week.
Cabinets, wiring, contacts, and other alternator components continue
to be inspected and refurbished.  Alternator lube oil has been
collected and send out for analysis.  Work has started on the
installation of a sliding gate which will allow more efficient access
to the electrical equipment located under the alternator. A Kirk lock
system will be installed on the gate to ensure safe operation.


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

Additional brick fit-up and inspection of PPPL couplers #2 and #3 were
required, and have now been completed. We plan to plate these
components this week.  Coupons needed to continue testing of Au:Ge
braze material were plated last week and are ready to be used.

Work continued on new rf probe, phase and amplitude control, and
temperature control systems for the lower hybrid launcher.  Work on
software to interface lower hybrid control and MDSplus software also
continued.


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

Components needed before the installation of the J-Port antenna can
begin are complete.  Components have been mounted onto the new J-Port
flange and a successful leakcheck has been performed.  We plan to
begin installation of the antenna on C-Mod this week.

Work continues on preparations for high power tests of the fast
ferrite tuner. The power supplies, card cages and demodulators have
been rack mounted.  Other required components are on order.


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

The design of a frame to support an in-vessel linear polarizer that
can be rotated into the MSE optics' field-of-view has been completed.
This frame will provide a source of linearly polarized light of known
polarization for use in directly measuring the Faraday rotation of all
MSE optics at full field.

Ron Bravenec, U. Texas, visited MIT and PPPL last week.  He acquired
and polished the ends for 18 additional optical fibers for the BES
system.  The fiber holder modifications to accommodate the new fibers
are the next step.  When completed, some BES fibers will be
close-packed for high resolution measurements in the region of the
quasi-coherent mode, while other fibers will maintain the present
resolution further in to the plasma.


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

Steve Scott was at PPPL 9/7 and 9/8 for discussions with Fred
Levinton, Brent Stratton and Jill Foley regarding MSE analysis.

Ron Koontz, SLAC Klystron/Microwave Center, was at MIT on 9/10 to
discuss klystron refurbishment and maintenance processes.  He provided
important insights into klystron operational issues.
/

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