Alcator C-Mod Weekly Highlights June 28, 2004 FY 2004 weeks of operation planned: 18 weeks, completed: 18.9 weeks. A report has been submitted to DoE confirming completion of our third quarter level 1 Joule sub-milestones: SC7-a Achieve total operating weeks as planned for FY2004: C-Mod, 18 weeks. Sub-milestone: Achieve level of facility operation consistent with baseline plans and meeting total operating weeks for FY2004. SC6-1b Compare energy confinement, H-Mode thresholds, and divertor particle dynamics in Alcator C-Mod discharges Sub-milestone: Explore H-Mode threshold for double-null discharges SC6-1e Complete design of ICRF antenna for C-Mod Sub-milestone: Complete thermal analysis of preliminary design We are currently up-to-air with the primary goal of installing the lower hybrid launcher. In addition, a large number of invessel activities are ongoing in support of ICRF and diagnostic systems. Maintenance and upgrades to diagnostic and power systems are also in progress. Operations ---------- Three new links have been added to our websites. The current listing of high priority experiments can be found at: http://www.psfc.mit.edu/people/wolfe/cmod/experiments_fy04.html A summary table of the research done thus far in FY04 can be found at: http://www.psfc.mit.edu/cmod/operations/FY04_research_table.html Day-by-day and shot-by-shot tables of test and run days completed, and discharges produced, since the beginning of the project can be found at: http://psfcsv1.psfc.mit.edu/cmod/cmod_runs_db.php We continued work on upgrades to our PLC to PC interface software. The CRYO system will be the first to be upgraded and work has concentrated on this system. Invessel work last week focused on a cleanup of all invessel surfaces. Tile modules are being removed and all tile surfaces, hold down hardware, and support plates are being carefully cleaned to remove residue left from boronization and plasma operation. The vessel walls are also being cleaned. A hole has been drilled through the cell wall for the long pulse DNB power conduit run. A 15 kV disconnect has been removed from the power room to make room for the new DNB transformer. The new transformer is expected in-house this week. Work at B-Port Horizontal to prepare for the 8th non-axisymmetric control coil installation has been completed. We expect to install the new coil this week. The POs for fabrication of the new B- and J-Port flanges have been processed. ICRF Systems ------------ We continued testing of the FMIT#3 and #4 transmitters at 50 MHz. The performance of these systems at 50 MHz during the last run campaign was not what was expected, particularly for the FMIT#3 transmitter. The input impedance to FMIT #3's FPA was found to vary widely with slight adjustments of ferrite positions, often yielding multiple resonances. This effect may be the source of the instability that was experienced during the run campaign. This condition does not exist on either of the tunable transmitters at 70 MHZ or 78 MHZ, or on FMIT #4 at 50 MHz. Filters have been ordered to trap any harmonic or spurious RF which may have complicated tuning at 50 MHZ. Lower Hybrid Project -------------------- New 3-window prototypes are in-house and a braze test with the new windows and coupler corner radius will be completed this week. These prototypes will also be used to test lower temperature brazes that can be used for coupler repairs. Procurement of the first 140 windows needed to complete brazing of the MIT couplers is still on schedule. Several more waveguides in the fwg/rwg launcher assembly have been tested successfully. A total of fourteen of the upper twenty-four guides have reached full performance operation at 100 kW for 0.5 s. There are a total of 48 input guides to be checked on the launcher. We have been checking guides at the rate of between 5 and 8 per day. All twelve of the new klystron vac-ion pump controllers have been installed and tested. Signals for these new vac-ion pump controllers have been included in the LH operator interface graphical program. Two signals from each of the controllers are monitored by the transmitter PLC program; the HV on digital signal, and the vac-ion current recorder output analog signal. We continue to develop the probes needed to monitor rf performance in the launcher while adding another layer of fault protection. The microstrip pc board files have been sent to several vendors for a quotation. EDM work on the first three prototype probe housings has been completed with delivery expected this week. All lower hybrid SFOL channels are now working and ready for operation. Power Systems ------------- The 120 gate-drive boards that were removed from the TF power supply for an upgrade have been completed and tested. They will be tested again following installation in the TF convertor cabinets and before we resume operation. We continue maintenance work on the MIT alternator. Filtering of the lube oil is in progress. Refurbishment of th 2000 HP motor, cooling water system, and contactor panel is underway.