Alcator C-Mod Weekly Highlights
			    December 26, 2006


FY2007 weeks of research operations:
   tentative target: 15 weeks
   Completed: 0 weeks


The C-Mod First Quarter DoE non-Joule milestones are complete and
reports on these milestones have been submitted to DoE:

A.1 Complete tests on and evaluation of prototype cryopump,
including cool-down with liquid nitrogen and liquid helium, measuring
pumping speeds for deuterium and hydrogen, and exploring regeneration
cycling. (December 31, 2006)

B.1 Complete refurbishment of Lower Hybrid High Voltage Power Supply,
and prepare to operate klystrons. (December 31, 2006)


Physics
-------

ELMs have a significant effect on the ICRF antenna loading. From the
loading variation, Yijun Lin has identified both primary and secondary
ejections due to ELM activities. The loading variations during ELMs
are faster than those in H-L transitions, but have similar
magnitudes. These data can be used to benchmark antenna codes, and help
to provide more insight into ELM activity and effects.


Operations
----------

A great deal of work was done last week at F-Port on DNB-related
diagnostics and preparations for Long Pulse DNB re-installation.  The
modified F-port flange has been installed, torqued, and leak-checked.
The installation fixture has been removed, opening up the floor space
for the DNB.  The FRCECE mirror, internal waveguides, and vacuum
flange have been installed.  The in-vessel MSE optics canister has
been re-installed, along with the shutter push-pull cables, and the
MSE low-Verdet glass window.

The in-vessel table needed to support the cryopump during the
in-vessel welding process is in-house.  The LHe manifold for the
Inconel 625 inner LHe cryopump tube has been welded onto the tube and
successfully leak-checked.  All ten new Rogowski coils needed to
diagnose the upper chamber are ready for installation.

We continued work on CXRS, Science Surface Station, polarimetry, and
bolometry diagnostic activities.


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

Work continued on the Coupler Protection System (CPS) upgrade and the LH
klystron test stand.  Investigation of a fault in one of the klystron
circulators is underway.


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

Last week modifications were completed to D and E antenna to improve
voltage handling by reducing the rf electric field component along the
toroidal magnetic field in the vacuum transmission line.  The antennas
are now ready for re-assembly.  We also completed disassembly of one
of the Fast-Ferrite-Tuners as part of an inspection and to identify
locations where improvements could be made.  The ground plane will be
reinforced to improve the rf voltage standoff potential and to reduce
other non-ideal effects.  In addition, careful measurements are being
made of the FFT to properly document its construction and supplement
the vendor's drawings.
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