Alcator C-Mod Weekly Highlights
			July 18, 2005

FY2005 weeks of research operations
Planned: 17 weeks
Completed: 12.5 weeks

Operations
----------

Last week was a scheduled maintenance week at Alcator C-Mod. No plasma runs
were planned or completed. 

The main purpose of the maintenance week was to retune half of the ICRF
sources and reconfigure the J-port 4-strap antenna for operation at 50 MHz,
primarily for He3 minority heating studies at 5 tesla. We also plan to carry
out H minority heating investigations at 3.5 tesla, as well as mode
conversion
RF experiments. 

Preventive maintenance was carried out on the alternator oil heat exchanger
system, and the alternator was returned to service.

A brief argon backfill and clean vent was performed on the C-Mod vacuum
system
to successfully repair a leaking gate valve on the Compact Neutral Particle
Analysis diagnostic.

Plasma operations are scheduled to resume this week.

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

FMIT#3 and 4 transmitters were retuned from 78 MHz to 50 MHz operation. The
J-port antenna transmission line network was also reconfigured for 50 MHz. 

In the FMIT#1 transmitter (D-port dipole antenna), problems with the crowbar
trigger circuit were corrected and LED indicators were installed to provide
additional status confirmation.

Long Pulse Diagnostic Neutral Beam
----------------------------------

On Monday morning, a problem with the DNB cathode heater was traced to a
broken tantalum strap.  In the process of ion source disassembly to assess
the
problem, evidence of arcing in the source was also seen. A new heater
assembly
is expected to arrive from the Budker Institute in the coming week, and we
have ordered the tantalum required to repair the broken strap on the
heater. The beam designers at Budker recommend increasing the water flow to
the source to provide additional cooling and thus decrease the amount of
strain due to thermal expansion.

Preparations are being made for Dr. Petr Deichuli and Mr. Gregory 
Shulzenko to visit MIT to assess the beam performance and to assist in 
tuning the beam for higher beam current. 

Quarterly Review
-----------------

The third C-Mod Quarterly Review of FY 2005 was held at the PSFC on
Thursday,
July 14. Attending from OFES, DoE were Adam Rosenberg, Rostom Dagazian, Erol
Oktay, and John Mandrekis.  Randy Wilson and Dale Meade also attended by
videoconfernce from PPPL.  Presentations on the status and results of the
C-Mod program were made by S. Wolfe, Y. Lin, R. Parker, J. Irby, R. Granetz,
and B. LaBombard. Also attending at MIT were E. Marmar, S. Scott, W. Rowan,
M. Porkolab, J. Rice, P. Catto, P. Bonoli, N. Basse, A. Hubbard, and D.
Ernst.
Viewgraphs of the presentations are available at
http://www.psfc.mit.edu/research/alcator/pubs/quarterlies.html

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

Nevell Greenough and Jay Kung, PPPL, were at MIT last week to work with Ron 
Parker on low power phase calibrations of the lower hybrid launcher.



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