Alcator C-Mod Weekly Highlights April 17, 2012 FY2012 weeks of research operations Target: 17 Completed: 5.6 Plasma Shots: 753 Operations ---------- Following several inspections and extensive documentation of the in-vessel components, C-Mod was pumped down on Wednesday, 4/11. The vessel has been undergoing a 120 C bake since Thursday, 4/12. In preparation for plasma operation, a high pot of the C-Mod magnets at room temperature indicated very high isolation of the magnets to ground. This measurement will be repeated when the magnets are at liquid nitrogen temperature. Routine maintenance of the magnet power supplies and alternator systems has been completed, and these systems are ready for operation. The C-Mod infrastructure computers, both LINUX and Windows, have been moved from the control room to a new dedicated computer room. All systems are back on-line. The PSFC web server has been upgraded to a 24 core / 16G server, and moved to the NW16 computer room. ICRF Systems ------------ The E-Port antenna FFTs have been reinstalled in the cell and have been reconnected. We have begun preparations for the new FFTs to be installed in the D-Port antenna transmission line network. We have completed a dry nitrogen purge of the field aligned J-Port antenna transmission line. The relative humidity of the line is <2% and it will soon be pressured with SF6. We have begun installing the waveguide run for the scrape off layer reflectometer at H-Port that will measure the SOL density profile at the field aligned J-Port antenna. Lower Hybrid Systems -------------------- Water cooling, filament control, and other lower hybrid systems are being brought back on-line in preparation for plasma operation. Phase and amplitude calibrations are being confirmed. Diagnostics ----------- A new periscope viewing the low-field side edge plasma was installed during the up-to-air. This periscope will collect light resulting from charge exchange of boron with deuterium neutrals (Charge eXchange Recombination Spectroscopy, CXRS). Deuterium neutrals are created when a D2 gas puff, fed from a gas capillary located on the outer-wall, interacts with the plasma. This periscope will complement the existing poloidal periscope viewing the same gas puff, allowing determination of the velocity vector (ignoring small radial velocities) and radial electric field, since the poloidal periscope includes views for D-alpha measurements to calculate the boron density from CXRS brightness. Remote Participation, Travel, and Visitors ------------------------------------------ Paul Bonoli, Anne White, and Dennis Whyte attended the 2012 Sherwood Meeting in Atlanta, GA, from March 31 to April 3rd. Their presentations can be found at http://www.psfc.mit.edu/research/alcator/pubs/Sherwood/Sherwood_2012_abstracts.htm The TTF meeting was held in Annapolis, Md, from April 10 to 13. Many C-Mod scientists attended including Catherine Fiore, Miklos Porkolab, Amanda Hubbard, John Rice, Jerry Hughes, Anne White, Nathan Howard, Yunxing Ma, John Walk, Ken Liao, Paul Ennevar, Darin Ernst, Mike Churchill, Ralph Kube, Evan Davis, Matt Reinke (ORISE), Istvan Cziegler (UCSD), Bill Rowan (UT-FRC), Ken Liao (UT-FRC), and Igor Bespamyatnov (UT-FRC). Presentations can be found at http://www.psfc.mit.edu/research/alcator/pubs/TTF/TTF_2012_abstracts.htm Martin Greenwald and Josh Stillerman met with Allen Razdow of True Engineering Technology LLC to exchange ideas and explore concepts for tracking data provenance and providing work-flow documentation. Jerry Hughes was in Annapolis, Md, last week to co-chair the Edge Coordinating Committee Spring Technical Meeting. Amanda Hubbard, Dennis Whyte, and John Walk also attended this meeting. Yijun Lin traveled to Hefei, China, last week to begin a ten day visit to participate in ICRF operations and experiments on the EAST tokamak facility. David Gates, PPPL, gave the PSFC seminar last week on the "Origin of the Greenwald density limit." He had discussions while here with Steve Scott, Luis Delgado-Aparcio, Miklos Porkolab, John Wright, Jay Kesner, and Linda Sugyama. _______________________________________________ Cmod_weekly mailing list Cmod_weekly@lists.psfc.mit.edu http://lists.psfc.mit.edu/mailman/listinfo/cmod_weekly