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



Alcator C-Mod Weekly Highlights
January 3, 2000


Work progressed on all major projects last week even with time off
for the holidays. Transmitter, antenna, DNB, and invessel activities
all moved forward.


Engineering:

All copper plating for the RF antennas was completed successfully last
week. These components are now being baked in preparation for
installation invessel. Difficulties in fitup of the 4-strap antenna
have delayed somewhat the installation of this antenna. PPPL is sending
up engineering support to help with this effort. We also continued work
on the new boron nitride tile design for the E-port antenna. FEA stress
analysis of the boron nitride tiles indicates the support hardware is
more than adequate. We are ready to fabricate these tiles now that the
boron nitride material is in house.

The water cooling systems for fmit#1 and fmit#2 have been made operational
and tested. We are also making progress on the #3 and #4 cooling systems.
The fmit#2 FPA has been disassembled so that modifications can be made to the
input cavity to eliminate arc damage in this region. The 2274 tube that goes
in this cavity, on loan from DIIID, will be replaced with another 2274 just
returned to us from CPI.

We continued testing the DNB Mod/Reg into a dummy load last week. A
spark gap across the dummy load is being used to simulate an arc down
condition in the neutral beam source. This setup allows the Mod/Reg and
MCL timing, protection, and control electronics to be tested. Work has
also begun on bringing up the DNB CAMAC control and data acquisition system.

During the last run period valuable information about the scaling of the
inner vessel wall deflection as a function of halo current during
disruptions was gathered by the rangefinder diagnostic. Work is continuing
on upgrading this system to include five more retro-reflectors. Other
invessel related work included determination of locations for the new
invessel pressure gauges and their associated cabling. We also continued
work on repairing the H-port flux loop that was over heated by the ECDC
microwaves during the last run campaign. However, most invessel work last
week was still focused on re-installation of the three ICRF antennas.