Alcator C-Mod Weekly Highlights March 7, 2003 We continue to complete invessel work in preparation for pumpdown. Work also continues on ICRF and Lower Hybrid MIE Project systems. Machine instrumentation is being brought back on-line. Physics ------- Stewart Zweben, PPPL, gave a talk at the C-Mod physics meeting on edge minority heating for H-mode control. This talk described how minority heating near the edge of C-Mod plasmas might be used to generate fast ion loss and so control the edge radial electric field and the H-mode transition. Topics discussed were: previous work, edge resonance conditions, tentative experimental plans, diagnostics and analysis. Initial simulations of Er by C. S. Chang were also discussed. Operations ---------- Work has concentrated on invessel work this week as we approach pumpdown. The J-Port horizontal flange has been reinstalled and installation of the antenna will begin as soon as all the rf vacuum feedthroughs are installed and leakchecked. We continued work on the MHD antenna, glow discharge cables, invessel alignments, and installation and testing of invessel cabling. The machining of the new BN tiles for the J-Port antenna has been completed. We continue the migration from VMS based to linux based data acquisition software. Data system diagnostic routines used on the VMS based system now work under linux. Data highways and user software are being tested and prepared for full data acquisition shot cycle tests. Machine instrumentation is coming back on-line in preparation for pumpdown, vessel bake, cooldown, and ECDC. Machine information is again being trended to the MDSplus tree. Lower Hybrid MIE Project ------------------------ At MIT, we continue to bring transmitter protection and control systems on-line in preparation for high power klystron tests. The data acquisition equipment and software have been tested successfully. More parts for the active controller equipment chassis have been ordered, as backplanes for the chassis are being populated. At PPPL, cleaning of the LHCD coupler ceramic vacuum windows has been completed, and the inner metallic surfaces are now being copper plated. The vacuum waveguide assembly has been successfully inserted into the port extension for a trial fit-up. More polishing of the launcher rails is needed for a smoother surface finish and an easier movement of the launcher. Mounting of standard waveguide components onto the rear waveguide assembly has started. ICRF Systems ------------ The process of developing a detailed cost and schedule plan for the fast ferrite tuner project has begun. Based on response time and required magnetic field, preliminary specifications for the power supply for the electromagnet have been developed. Measurements of the ferrite losses are underway. MSE Diagnostic -------------- All fabricated components for the refurbished Motional Stark Effect diagnostic have been received at MIT. Shake testing of the new mirror support frame has confirmed that the mirror is now capable of surviving accelerations of 1700 g in both the longitudinal and out-of-plane directions, which far exceeds the expected disruption-induced accelerations. Final vacuum baking of several components will take place over the weekend. Final assembly, installation, and alignment will be performed on Monday, in anticipation of close-up of C-Mod mid-week. The INCONEL 600 backup metal mirrors for the MSE diagnostic are in-process at PPPL. Once machining operations are completed at PPPL, the mirrors will be sent to one vendor for polishing and then to a second vendor to be coated. Travel and Visits ----------------- Martin Greenwald and Miklos Porkolab traveled to Washington DC to attend a meeting of the Fusion Energy and Science Advisory Committee. The principal issues at the meeting were a discussion of the 2004 budget, US ITER participation, and the 35 year development plan.