Alcator C-Mod Weekly Highlights May 10, 2002 The cryostat was installed this week marking a milestone in the reassembly of Alcator C-Mod. Work continued on ICRF, LH MIE, DNB, and diagnostic systems. Operations ---------- A successful hi-pot and ring was done this week on all the C-Mod magnets. This step marks the "tokamak complete" stage of reassembly. Earlier in the week, all connections between the curved bus and the coax extensions were completed and inspected. All cooling lines have been run from the tokamak to the manifold above the bus tunnel. Following a last set of inspections, the lower cryostat was raised, allowing access to the lower vertical ports. Installation of instrumentation below the machine is now well underway. Later in the week both the upper cryostat and the cryostat cover were installed. A picture of the top cover being installed can be found at http://www.psfc.mit.edu/cmod/operations/EngImages/Inspection_2001-2002/Disassembly_Assembly/Machine_assembly_B/DCP_0659.JPG Three of the new instrumentation ports can be seen near the middle of the photo. The boots that will soon seal the cryostat are also shown surrounding the horizontal ports. Following installation of the rf feedthroughs at D- and E-Hor earlier in the week, installation of the ICRF antennas has proceeded quickly with final assembly expected by early next week. The BN tiles have been vacuum baked at 400C, cooled down, and are ready for installation. The TORVAC pumping station is being brought back online. CAMAC highways and PLC communications are being brought back up, as are the control room workstations. Seven more Linux workstations were received early in the week and are now available for use in the control room. Work on the magnet bus, TF/TC scanners, and ECDC systems also continues in preparation for the next run campaign. Lower Hybrid MIE Project ------------------------ Two engineers from the power supply vendor will return next week to begin commissioning of the HVPS. Tests conducted at the vendor site indicate that software problems with the control program have been fixed. Components needed for the forward and reflected power measurements have been selected and are now on order. Work continued on the PLC control system timing for the up coming transmitter tests, as well as the low power realtime control system. The PPPL May Fin Plan Letter has arrived with $300K additional budget authority for the C-Mod Lower Hybrid Project. This amount is being borrowed against planned FY2002 diagnostics, which will be deferred, and will be returned out of FY2003 LH funds. We now have authority to spend that budget and accelerate the final design and FY2003 procurements for the LH launcher. ICRF ---- We continue to build up the new racks and control, fault, and diagnostic electronics for the transmitters. Hi-yard work is ongoing to ready the transmitter high voltage supplies for operation. New control electronics for the tuners and phaseshifters is becoming operational. RFX DNB ------- The DNB racks, control computer, and PLC were repositioned so that all the DNB equipment is now in its final position. PLC control and monitoring is now being done from the control room. Equipment is now being prepared invessel and on the DNB beam line to align the beam relative to the tokamak. The components needed for the LN2 feedline for the DNB and cryopump from our main storage tank have been ordered with delivery expected in 3 to 4 weeks. We will continue to operate the beam using LN2 from 500l dewers until the new line is installed. All gas delivery components are in-house, and the beamline duct that connects the beam to Alcator C-Mod is undergoing leakchecks. Diagnostics ----------- Installation and alignment of CXRS, MSE, and BES invessel optics has been completed. Spatial calibration is partially complete. All calibrations will be completed next week. The MSE diagnostic image dissector has been returned to MIT from PPPL. This is a new design that is much more efficient optically and operationally than the original image dissector, and is the last of the modified optical system components. The bolometer array at K-Hor was re-installed this week and will be calibrated over the next few days. Travel and Visits ----------------- Matt Sampsell, UT-FRC, visited during the week and assisted with the invessel installations. Stew Zweben, PPPL, worked on the Gas Puff Imaging diagnostic at MIT 5/9-10 and gave a seminar, "Edge Turbulence Imaging In Alcator C-Mod and NSTX," on 5/10.