Alcator C-Mod Weekly Highlights
                        April 26, 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
----------

All tungsten tiles have been removed from the outer divertor modules,
and we are making preparations to install molybdenum tiles at these
locations. In-vessel calibration of the MSE optics began last week, and
will continue this week. Calibration work for the bolometer, CNPA, and
visible bremsstrahlung diagnostics was completed last week.


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

Tests of the lower hybrid launcher radial drive mechanism and a final
leak-check were successfully completed last week.  The launcher has been
moved into the cell and is being connected to the jungle gym that
distributes power from the klystrons.  Shims needed to adjust the
column-to-column phase of the coupler are being installed and verified
for proper operation.

The new digital fiber optic modules for the Transmitter Protection
System and the rf probe calibration algorithm have both been tested
successfully.



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

FMIT#4 has been tuned to 78 MHz and the driver is running into a dummy
load at the 100 kW level.  This transmitter will be used for the rf
breakdown experiment.  We continued development of the RF Master Fault
Processor board.


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

New tools for HIREXSR spatial and spectral analysis are being developed
which will allow better integration with the MDSplus data system and the
existing GENPOS and GENSPEC tomography codes. The goal is to have the
new analysis code working when physics operations resume this summer,
and data from March 2010 analyzed by early fall.  Calibrations performed
both during and following the most recent operations period suggest that
HIREXSR spectra collected after March 10, 2010, are less affected by
vignetting after improvements to the spectrometer alignment were
made. However, the new analysis routines must still take account of this
effect.

We continued installation of the C-Mod polarimeter.  Both the upper and
lower enclosures can now be purged to sufficiently low moisture levels
to allow propagation of the FIR beams.  Development of low noise
detector amplifiers also continued.


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

Greg Hanson of Oak Ridge National Lab visited from Tuesday to Wednesday
last week. He worked with Cornwall Lau on the electronics of the SOL
reflectometer.

Wayne Solomon of PPPL visited PSFC on Friday. He gave a PSFC seminar on
"Investigation of Rotation Generation and Damping on DIII-D". He also
had discussions with John Rice, Bruce Lipschultz, Dennis Whyte, Ron
Parker and Darin Ernst during his visit.

Jerry Hughes participated remotely via video conference in the ITPA
Pedestal Topical Group meeting in Naka, Japan, 21--23 April 2010. The
chief focus of this meeting was an evaluation of techniques for large
ELM avoidance in ITER. He presented recent I-mode results from C-Mod, as
well as the status of three ITPA joint experiments in which we
participate.

Paul Bonoli attended a meeting of the ITPA Integrated Operations
Scenario Group this week at PPPL from April 20-23, 2010. He gave three
talks at the workshop entitled:

"GENRAY-CQL3D Simulations of LHCD Experiments in Alcator C-Mod including
a SOL", P. T. Bonoli for G. Wallace.

"LHCD Simulations for the Modified ITER Scenario 4 Case", P. T. Bonoli,
for R. Prater, J. Garcia, and M. Murakami

"Proposal for How to Proceed with Benchmarking of ICRH Codes",
P. T. Bonoli


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