From: irby@PSFC.MIT.EDU
Reply-To: IRBY@PSFC.MIT.EDU
Subject: Alcator C-Mod Weekly Highlights
Newsgroups: sci.physics.plasma


Alcator C-Mod Weekly Highlights
February 1, 2002

Reassembly continued on Alcator C-Mod this week. Work on the LH MIE
Project, preparations for the new RFX beam, and work on ICRF systems
also continued.


Physics
-------

Data was presented at the Physics Meeting this week showing the time history
of the Balmer H-to-D ratio over several C-Mod campaigns. An increase in
this ratio was seen to be well correlated with installation of boron
nitride tiles on the ICRF antennas. Maintaining a low H-to-D ratio is
important on C-Mod where ICRF fast wave minority heating is the primary heating
scenario. We are now investigating the best way to reduce the level of
hydrogen generated by the tiles, so that better control of this parameter
can be obtained during the next run campaign.


Operations
----------

All twenty lower TF arms have now been installed. Installation of the
springplates using the new hydraulic insertion tool is expected to begin
next week. The MIT funded upgrade to the cell air conditioning continued
this week with installation of the mounting hardware for the new cooling
unit, and rework of the ventilation system. Work continued on preparations
for cylinder machining.


Lower Hybrid MIE Project
------------------------

Initial tests were completed on transmitter #3 protection, control, and
supply cabinets. The cabinets were installed in the cell underneath cart #3.
Testing was begun on the protection and control cabinet for transmitter #2,
and the control and supply cabinets for transmitter #1. Cart #2 has been
installed in the cell on the upper mezzanine. Two of the three carts required
for LH Phase I are now in the cell. Pre-installation testing was completed
on transmitter cart #3. This cart will be installed in the cell once all
other equipment racks have completed testing.

The high-voltage junction box for the HVPS was hi-potted along with the
triaxial cable and the dummy load. Both the high-voltage enable and trigger
gates (fiber-optic to the HVPS) are now operational. Wiring between
transmitter cart #3 and its associated equipment racks was begun.

PLC Operator console display screens were designed or modified for,
transmitters #1 and #2, the coolant system, and the HVPS.


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

We continued in-house machining of the D and E-Port Faraday screens, and
the J-Port current straps. Work also continued on phase detection and
fault electronics.


DNB and Related Diagnostics
---------------------------

Modifications to the DNB support stand so that it will interface properly
with the new RFX beam are nearly complete. The transformer tank
supports on the upper level stand are complete. The chamber supports on the
mezzanine level have been installed.

Modifications to the PLC rack are near completion. Testing of
the control power and signals began this week. Testing through the PLC
will begin next week.

The new F-Port flange design has been sent to a vendor for fabrication.

We expect the Russian team to arrive in Boston on the 17th of February to
begin installation of the RFX beam.


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

Martha Redi was here this week from PPPL working with Catherine Fiore
on GS2 analysis of dual frequency ITBs on CMOD.