Alcator C-Mod Weekly Highlights November 29, 2004 FY 2005 weeks of research operation planned: 14 weeks, completed: 0 weeks. We are currently up-to-air with the primary goal of installing the lower hybrid launcher. In addition, a large number of in-vessel activities are ongoing in support of ICRF and diagnostic systems. Maintenance and upgrades to diagnostic and power systems are also in progress. Physics ------- The C-Mod Ideas Forum will be held December 2-3, and 6. Because of the very large number of proposals, we will extend the Forum for a third day, from the original plan of two days. A list of proposal titles can be found at http://www.psfc.mit.edu/cmod/sciprogram/ideas2005/TitleList.htm Instructions for remote viewing of the forum will be posted at http://www.psfc.mit.edu/cmod/sciprogram/ideas2005/remote_access.html Operations ---------- Work continued on ICRF, Lower Hybrid, and in-vessel systems last week. The 2Pi bolometer, the bolometer array, and the gas baffle for the j-bottom gas puff have been installed in-vessel. Nine W-brush tiles have been sent to Sandia, Albuquerque to be brazed. Brazing will increase the thermal contact between the W rods and the stainless steel support plates. ICRF System ----------- The refurbishment of the eight power modules and UPS system for the Fast Ferrite Tuner was completed last week. Module testing and documentation will continue this week. Lower Hybrid System ------------------- The forward waveguide (fwg) with the #1 and #2 PPPL couplers installed is being baked under vacuum in the vacuum test stand. An initial leak-check at temperature indicated a small leak. We are refining the leak-check procedure to isolate the location of the leak before coming up to air to repair it. We are continuing to develop procedures aimed at repairing waveguide leaks in the #3 and #4 PPPL couplers, while also preparing for braze operations on the #4 MIT coupler. A borescope has been used to verify that the rf probe boots are seated properly in the fwg at all 192 probe locations. Fabrication of the probe housing continues. Calibrations and program development for the klystron phase and amplitude control and interlock systems continued last week. The optical interface board for the TPS to CPS interface has been ordered. The remaining CPS chassis wiring is being completed by the Electronics shop. Work continues on the klystron test stand. Two pulse capacitors for energy storage at the primary side of the pulse transformer have been ordered. An available high voltage power supply, suitable for use on the test stand, has been identified at the PSFC. We have also located an equipment rack, and all control and power electronics are in the process of being rack mounted. Long Pulse DNB -------------- Additional floor space for a line side inductor to be installed with the new DNB has been requested by the vendor. The removal of the de-commissioned water chiller unit in the cell has cleared enough room for the DNB PLC rack and the new inductor. Work is ongoing to improve the space by moving the water chiller monitoring electronics from a position on the floor beam to a better location on the cell wall. Conditioning of the new beam continues to go well in Novosibirsk. The beam is currently running at 50 kV, 5 A, with a markedly reduced water fraction compared to earlier measurements. Beam parameters of 50 kV at 7A are expected when conditioning is complete. Travel and Visits ----------------- Houyang Guo, U. Washington, visited on Monday for discussions with C-Mod scientists; he presented a seminar entitled "Edge transport barrier in JET ELM-free hot ion H modes". He also discussed his work on RFCs. Manfred Bitter, PPPL, and Sang Gon Lee, KSTAR, were here last week (Friday-Monday) to align and calibrate the imaging curved crystal spectrometer, to be used for viewing He-like neon. This work took place mainly over the weekend in collaboration with MIT graduate student Alex Ince-Cushman. Martha Redi visited Alcator C-Mod November 22-24 to work with Catherine Fiore in preparing a mini-proposal for the Ideas Forum 2005 and discussion of new microstability calculations. Stefano Coda, TCV, visited last week and presented a seminar on "High-bootstrap, Non-inductively Sustained Electron Internal Transport Barriers in TCV". He also discussed his PCI work on DIIID, particularly high-k measurements, with Nils Basse and the PCI group. Dr. Olaf Grulke, a visiting scientist at C-Mod during all of 2003, visited us again last week. During the week, he worked with Jim Terry on post-processing the results of a 2D turbulence code. He also discussed with B. Lipschultz, B. LaBombard, M. Greenwald, and J. Terry ideas for future experiments and collaborative efforts. Dr. Grulke will be continuing his collaboration with another on-site visit for a few months during 2005. Dr. Grulke is affiliated with Max-Planck-Institute for Plasma Physics in Greifswald and Christian-Albrechts-University in Kiel, Germany. _______________________________________________ Cmod_weekly mailing list Cmod_weekly@lists.psfc.mit.edu http://lists.psfc.mit.edu/mailman/listinfo/cmod_weekly