Alcator C-MOD Weekly Highlights April 1, 1997 Even with a major blizzard causing a slowdown in work, good progress was made in C-Mod reassembly. We have completed all magnet bus installations and the associated inspections, hi-pots, and ringing tests. All magnet cooling lines have been installed and verified for proper operation. The cryostat has been completed and sealed. The middle tier igloo blocks have been installed, and diagnostics requiring support from the igloo are now being brought back on line. Upper and lower crosses have been installed, and periscopes, probes, magnetics and MHD connectors, divertor thermocouples, and glow discharge feedthroughs and coaxes, which attach to the crosses, have been re-installed. Invessel alignments and calibrations continue. New shutters to protect optical components from the effects of boronization have been installed. Installation of power supplies for the off-line shakedown of the diagnostic neutral beam is well underway. Work continued on the design of controls for the new ACCEL supply and the associated crowbar circuit. The arc/filament/snubber supply was filled with filtered, degassed oil, and should soon be ready for further tests. Work on the magnet power supplies and new rf transmitters also continues. We are now bringing the TMX supplies, which power our EF2 and EFC magnets, back into operation. The control system for the new rf transmitters has successfully controlled the new tuners. We continue to make plans for in cell installations of rf components including coax runs and dc breaks. There was significant progress in the development of the DNB CXRS and MSE diagnostic systems. Since the CXRS optics are in the final design stage by UT-FRC, a meeting was held to ensure that all of the needs of the C-Mod experimental program would be met. The initial results of a feasibility study of MSE at PPPL was received and looks very promising. The vacuum interface for the UT-FRC Langmuir probe was successfully installed. This probe is optimized for edge turbulence measurements, and assembly of the probe itself is now being completed at the University of Texas. C-Mod has now contributed five shots to the ITER profile database. These shots included examples of ELM free H-modes, ELMy/EDA H-modes, reversed field L-modes (so called enhanced L-modes) and a normal L-modes. The new thermoelectric coolers for stabilizing the reflectometer Gunn diodes arrived at MIT from PPPL this week. Mike McCarthy from PPPL designed this system. Integration of the coolers into the reflectometer redesign has begun. Dr. N. Ohno (Nagoya Univ.) is visiting the PSFC Divertor Theory Group as a part of the US-Japan collaboration. Dr. Ohno, with PSFC scientists, will be analyzing data from the NAGDIS-II divertor simulator (Nagoya Univ.) for evidence of Molecular Activated Recombination. Jim Weaver and Ben Welch from the University of Maryland are visiting to help install there diagnostics on C-Mod and begin calibrations. Mark May and Vlad Soukhanovskii are here from JHU to complete installation of their divertor spectrometer. Joe Bartolick, Boris Grek, and Dave Johnson from PPPL are here to finish installation and alignment of the X-Point Thomson scattering system. Miklos Porkolab attended the Office of Fusion Energy Sciences lab director's meeting in Washington, DC.