NSTX Research Operation June 29, 2009 College W&M Colorado Sch Mines Columbia U Comp-X General Atomics INEL Johns Hopkins U LANL LLNL Lodestar MIT Nova Photonics New York U Old Dominion U ORNL PPPL PSI Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Irvine UCLA UCSD U Colorado U Maryland U Rochester U Washington U Wisconsin Culham Sci Ctr U St. Andrews York U Chubu U Fukui U Hiroshima U Hyogo U Kyoto U Kyushu U Kyushu Tokai U NIFS Niigata U U Tokyo JAEA Hebrew U Ioffe Inst RRC Kurchatov Inst TRINITI KBSI KAIST POSTECH ASIPP ENEA, Frascati CEA, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep U Quebec NSTX Supported by

NSTX NSTX Team Meeting June 30, Physics Operations going well Proceeding well with run Control –PCS control of NBI is ready for final testing next week This will allow Beta feedback to control NBI CHI –Successful coupling of I p > 100 kA to ohmic ramp-up –The absorber coils, PFAB, will be connected to SPAS They will be used to mitigate absorber arcs ISTP is imminent

NSTX NSTX Team Meeting June 30, Diagnostic upgrade status –Divertor bolometer ­Repaired electronics received at PPPL and checked out on the bench; will be installed this week and ready to operate next week –BES ­Fabrication and initial fit up of in-vessel components complete ­FDR of ex-vessel components held May 5; fabrication in progress ­Fiber SOW is out for bids ­UW making good progress on assembly of detector boxes ­On track for completion of installation during CY09 shutdown –MSE-LIF ­FDR for bay G port cover modifications held May 22; plan to modify port cover during CY09 shutdown ­Peer reviews held for design of DNB stand and DNB vacuum chamber ­Redesign of tangential bolometer nearly complete ­Bulk of installation will occur in CY10 shutdown

NSTX NSTX Team Meeting June 30, Diagnostic operations –Maintenance Activities ­Replacement of defective high voltage cables for JHU multi-energy tangential optical soft X-ray (ME-tOSXR) array ­Installation of camera for LLNL Long Wavelength Extreme Ultraviolet Spectrometer (LoWEUS) –Lyman-alpha Array ­Digitizer and detector amplifiers for new Lyman-alpha array received ­Diagnostic is under development as collaboration with LLNL for edge measurements in the vicinity of the NSTX liquid lithium divertor –X-ray Spectrometer ­Single-channel X-ray spectrometer installed on NSTX ­Instrument to be used to study plasma instabilities and monitor impurities during NSTX operations –NPA ­Received by Academia Sinica Institute of Plasma Physics (ASIPP) as part of collaboration involving plasma diagnostics

NSTX NSTX Team Meeting June 30, 2009  Fabrication of LLD-1 system in progress Laminated SS/Cu plates at vendor: moly coating starts 6/30; delivery ~7/15 Control rack preliminary checkout in cal lab completed Control software development in progress using heater mockup in vacuum  Liquid Droppers installed Unit-I and Unit-C installed. Unit-I controls done, Unit-C controls to be tested week of 7/6  LITER09 being used for ~80% of operations 5th reload completed; units parked in vessel behind shutters - loading on: 03/09/09; 04/18/09; 05/06/09; 05/31/09; and 06/16/09. On 05/31/09, only Bay F loaded.  Divertor Region Sample Probe yielding data Analyzed deposition in situ with Thermal Desorption Spectroscopy (TDS) Surface physics and chemistry of samples under analysis at Purdue Remote control tested and operative  UCSD Fast Probe upgraded Exchanged the head/shaft combo with a new one Installed newest generation of vacuum boards; more robust Tested all our data processing with the new MDS+ server Research Operation Division Boundary Physics Operations

NSTX NSTX Team Meeting June 30, Status of HHFW System and Edge Heating Results - Near Term HHFW Plans Antenna upgrade is complete and vacuum conditioning is starting Fast wave edge loss channel has been detected with fast camera Infrared camera measurement of heat flux to outer divertor plate indicates hundreds of kilowatts are being lost at elevated edge density for H-mode cases studied to date Plan to study this edge loss process versus edge density and I P (magnetic pitch) for L-mode and H-mode discharges this experimental campaign

NSTX NSTX Team Meeting June 30, Previous RF Feed Previous Ground New Ground Additional RF Feed HHFW System Upgrades in Should Double Coupled Power & Increase Resilience to ELMs 2009 Double-feed upgrade shifts ground from end to strap center.2009 Double-feed upgrade shifts ground from end to strap center. Lower strap voltage for a given strap current:Lower strap voltage for a given strap current: –Double power per strap for the same plasma load. –Permits larger plasma- antenna gap (lower load) ELM resilient system will be added in 2010 for H-mode operation.ELM resilient system will be added in 2010 for H-mode operation.

NSTX NSTX Team Meeting June 30, Fast waves propagating in the SOL are heating the tiles on the outer divertor plate  “Hot region is much more pronounced at -90° than at -150° -Edge power loss is probably greater at -90° -Also, suggests fields move away from wall at -150° along with the onset density  Time for “hot” spot to decay away is ~ 20 ms at -90° and ~ 8 ms at -150° P RF ~ 1.8 MW, P NB = 2 MW, I P = 1 MA, B T = 5.5 kG

NSTX NSTX Team Meeting June 30, Infrared measurements show significant RF power deposition in the hot zones CHI Gap RF Hot zone -90° -150° Infrared Measured Heat Flux Shot ( s s) Visible Camera with Subtraction IR results indicate several hundreds of kW deposited on outer divertor plate Deposition for -90° farther out along with onset density Edge outer divertor plate CHI gap IR view -90°