Alcator C-Mod Weekly Highlights March 15, 2002 Machining of the retaining cylinder was completed this week. Installation of the upper TF horizontal arms is also complete. The new RFX diagnostic neutral beam is operational. Physics ------- Pedestal comparison experiments continued on Thursday and Friday at ASDEX-Upgrade. This series of discharges aimed to match the dimensionless parameters of some 1 MA EDA H-modes on C-Mod; previous experiments were at lower current. Despite fairly good matches to the shape and plasma parameters, the AUG H-modes were either ELMy or ELM-free. Detailed analysis of profiles and fluctuations will be carried out during the upcoming AUG maintenance period. Operations ---------- All machining of the retaining cylinder is complete. It is now being prepared for installation. All upper TF horizontal arms have been installed and the springplates inserted. Modifications to the cryostat have been completed by our vendor. We expect the cryostat to be back on-site by early next week in time for fitups of the new boots needed to seal the cryostat to the vessel ports. Preps to the horizontal vacuum flanges continue as we prepare them for installation with the new boot configuration. The new F-Port flange welding is nearly complete. The upgrade to the alternator varistor bank has been completed. The MIT funded work on the control room is making good progress. The old control room wall has been removed, new doors installed, new AC units hung, and the support hardware for the new ceiling tiles is in place. Lower Hybrid MIE Project ------------------------ The fabrication of components for the lower hybrid launcher is on schedule. The vacuum shroud and interface flange have been completed by the vendor and are being shipped to PPPL. The 5 final couplers are EDM'd and ready for brazing to commence on site pending delivery of the ceramic windows. Testing on the prototype waveguide is proceeding; some adjustment may be necessary to optimize the splitting configuration. Drawing packages are continuing to be collected for RFQ packages in anticipation of accelerated funding. High voltage wiring and connections to the klystrons has begun and transmitter control wiring continued. ICRF Systems ------------ The stub tuner and phase control box fabrication was completed this week. Work has begun on changes to the PLC software to control these new systems. We continued to work on improvements to the rf control and fault systems. All machining and polishing operations on the J-Port antenna straps have been completed and we are preparing to send them out for re-plating. We have begun final grinding operations on the D and E-Port antenna Faraday screens. DNB and Related Diagnostics --------------------------- The RFX Beam was operated this week at 50 kV and 4A, with 50 ms pulses. A very large effort by the Russian visitors, and Texas and MIT personnel was required to bring on line in such a short time the power, vacuum, and control systems needed to operate the beam. The DNB camac crate and highway have been brought back into operation in preparation for synchronization tests and for measurement of the component mix next week. Polishing of the BES fibers was completed this week. New ferrules for the BES optical fibers have also been completed. Ferrules for the MSE fibers are still being fabricated. Diagnostics: ------------ The 132 GHz channel of the upgrade to the reflectometer is operational at PPPL, and bench tests are continuing. The Gunn diode frequency can be varied between 128 and 136 GHz. The 140 GHz channel, originally intended to be another swept channel, has been converted into a fixed frequency channel until its Gunn diode can be repaired. All components are in-house for the MHD antenna and assembly is in progress. We continue to develop a prototype amplifier to drive the antenna. Travel and Visits ----------------- Miklos Porkolab, Ian Hutchinson, Earl Marmar, and Ron Parker attended the FY2004 Budget Planning Meeting in Gaithersburg, MD, on March 12,13. The Alcator C-Mod presentation for this meeting may be found at http://www.psfc.mit.edu/people/censabella/bpm_2002_presentation.pdf Earl Marmar also attended the FFCC meeting on March 14 at Gaithersburg. Martin Greenwald travelled to Oberlin College this week to give a talk on "Turbulence and transport in magnetic confinement experiments" as part of the APS distinguished lecture program. Martin also travelled to PPPL to attend the ITPA meeting on global confinement and modelling. Plans for migrating the profile databases to MDSplus were discussed. Tom Fredian presented MDSplus tutorials at three ITPA workshops held at GA and PPPL over the last three weeks. The tutorials focused on the MDSplus remote access to the ITER Profile Database now being stored in MDSplus format in Culham, England.