1

XP601 Summary

H. W. Kugel

5/08/06

2

XP 601 Summary for Thurs 5/ 04/06Goal: Observe an effect

• A comparison discharge was developed with low LFS fueling( Inj2=11.5 TorrL and SGI=9.75 TorrL).

• 6 Ohmic He Conditioning discharges were applied to condition the walls

• 378 mg of lithium were evaporated. This was measured to be 477 A° on theBayH QDM.

• 120474, the first 1 MW D NBI ref shot following lithium deposition Exhibited: • 29% decrease in density relative to 464, • Peakedness change from 3.5 to 3.9, • Electron temp of 2 KeV for 1 MW, • Taue ~ 90 ms. • Xeus OVIII was the same for 474 but decreased for 475 and went to zero for the following 3 NBI shots.

3

XP 601 Summary for Thurs 5/ 04/06 (Cont)

• On the next shot (475) the density reverted to that of the comparisonshot but the some peakedness remained.

• After 476 HeGDC started being applied between discharges but the densitycould not be lowered below that of 464.

• An ohmic HeCond shot (482) was applied to attempt to test the effect ofgraphite pumping. 483, D NBI exhibited about a 10% decrease in density.

• Then 2 He Cond shots (484,485) were applied and the following ref shotshowed a much smaller change (~5%).

• The last 2 shots were used to reduce the outside gas fueling to zero andreplace with SGI fueling for lower density.

4

XP 601 Summary for Fri 5/ 05/06 Goal: a) Verify reproducibility of the effect

b) Determine the relative graphite and Li contributions• Additional comparison discharge development was performed.

• A reference discharge was performed before starting He Conditioning

• 6 Ohmic He Conditioning discharges were applied to condition the walls

• The ref discharge was applied an exhibited ~ 14% decrease in density.

• A lithium evaporation was attempted but a snout heater malfunction occurred

5

• Near Term Plan• Remove LITER1B from vessel (Wed morning)• Investigate replacing cartridge with either

• either new cartridge (2.5 wks)• or use cartridge 1C from L-245 (without air cooled shroud)

• Investigate increasing aiming angle from 22° *CS shoulder to ~16° (CS bottom)

• Issues• The Heater vendor suggests derating the max power by x4 (165 w to 660w) for vacuum service• Building new cartridge with upgraded heaters will require testing• Using Cartridge 1C without air-cooled shroud will cause local vessel heating and outgassing• Changing the aiming angle may not be possible during this Maintenance Week