Alcator C-Mod Weekly Highlights
                        April 5, 2010


FY2010 weeks of research operations
   Base Target: 13 weeks
   Base Completed: 9.7 weeks
   ARRA Target: 5 weeks
   ARRA Completed: 5.0 weeks
   Plasma Shots: 1630


Operations
----------

Alcator C-Mod was brought up-to-air last Friday after seven days of
warm-up, and all vessel surfaces had reached room temperature.  Two days
of glow discharge cleaning had been completed earlier in the week to
help reduce the levels of boron compounds formed during boronization.
Multiple up-to-air and pump-down cycles were also performed on Friday
which also helps reduce the levels of these compounds.


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

The vacuum bake of the lower hybrid launcher was successfully completed
last week.  The launcher passed leak-checks multiple times both while
hot and at room temperature.  A set of rf tests are planned for this
week.

Work continued on the Coupler Protection System (CPS), in particular on
circuitry required for long pulse operation.  A meeting was held last
week with our vendor for discussions on the Transmitter Protection
System (TPS).  The vendor delivered several new boards for the TPS at
the meeting.  The schedule for installation of the full TPS system was
discussed.


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

Disassembly and inspection of D, E and J antenna transmission line
networks have begun.  All of the new vacuum feedthroughs for the new
advanced ICRF antenna are in-house and are leak-tight.  Preparations for
power testing these components are being made.

The RF Breakdown Experiment vacuum chamber has also passed its
leak-check. This new experiment is designed to help us understand
breakdown processes associated with ICRF antennas.  The first set of
test samples were polished and await characterization.  We will begin
assembly of the ridge waveguide transmission cavity and prepare FMIT#4
to provide power for these experiments over the next few weeks.


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

We have received all of the components needed for the new automated MSE
alignment/calibration system.  Also, a new shutter system comprised of a
stainless steel optical housing and an Inconel 625 shutter has been
fabricated and gold-plated for thermal isolation.

The polarimeter lower optical table enclosure has been completed.
Instrumentation needed to monitor the pressure in the enclosure and the
flow rate of gas used for the purge is being installed.  A low humidity
atmosphere is required to keep attenuation of the FIR beams low.


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

Jeff Casey, Rockfield Research Inc, visited to discuss the Transmitter
Protection System with Dave Terry and other members of the Lower Hybrid
Group last week.

Rachael McDermott, ASDEX, IPP-Garching, visited last week and had
discussions on Er profiles and I-modes, among other topics, with several
C-Mod scientists including Bruce Lipschultz, Jerry Hughes, Amanda
Hubbard, and Matt Reinke.

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