Alcator C-MOD Weekly Highlights April 21, 1997 The Alcator C-Mod vacuum vessel is now being baked. Cooling of the magnets has also begun since they must be cooled with liquid nitrogen to an average temperature of -25C to protect them from the high temperatures. In addition, we have begun the slow cooldown of the domes and cylinder which are made up of about 175,000 lbs of stainless steel and require several days to cooldown to operating temperature. The bake will last most of this week, after which ECDC cleaning of the vessel walls will begin. We continue to install and align diagnostics. Much progress was made this week on the new RF systems. Coax installations both in the cell and the power room are nearing completion. New ignitrons for the crowbar circuits arrived and are being installed. Water cooling systems for the new transmitters are in operation and their temperature interlocks have been checked. HV anode cable conduits are being installed. The FPA cavity for transmitter #4 has been assembled and cavity position indicators for the driver/IPA have been calibrated. Power system checkouts continue. The bus instrumentation system is now operational, some of which is being used to control the magnet LN2 cooling. Preparations are being made for a review of changes to the power systems to be held early this week. Low current tests of power supply operation into the magnets are scheduled to begin later this week. We continued the installation of the DNB power supplies. Reassembly of the Mod/Reg continued, and we began to develop the design changes that are required to incorporate the new ACCEL supply. Control system design on the fast interface between the main control system, the ACCEL supply, and the crowbar continued. Those of you interested in viewing the new invessel diagnostics might check out the inspection photos at: http://www.pfc.mit.edu/cgi/cmod_images?name=invessel/ Rick Maqueda continued his visit from LANL last week working to install the new IR periscope. Joe Bartolick, Boris Grek, and Dave Johnson from PPPL successfully completed the Raman calibration of the X-point Thomson scattering diagnostic last week. John Gumpus and Gerd Schilling, also from PPPL, continued their work with our RF group helping to bring the new RF systems online.