Ex-1.1.7 Divertor W erosion and ELM induced sputtering G. V Rooij SC J.W. Coenen SC M.StampRef. SL
Scope of Experiment 1.1.7 • Development of methodology for routine characterization of W erosion in the divertor throughout the upcoming experimental campaigns: • Consistency check for different WI and WII lines in divertor plasma temperature and fluence scans in relation with presence of Be, C, and O. • Influence of reflective environment on spectroscopic measurements • Optimization and cross calibration of the different spectroscopic systems • Characterization of the baseline W erosion in JET in dependence of: • Divertor plasma conditions (temperature impact energy; density fluence; divertor fuelling/ impurity seeding) • Strike point position, i.e. Investigate difference between bulk W and W-coatings (HT3R versus L) • Plasma shape, i.e. Investigate influence of main chamber impurity production (VHi5_4M5_LT versus HT3) • Reconstruction of divertor WI and WII emissivity's to assess W redistribution • The experiments will differentiate between: • L-mode • H-mode inter ELM (Standard and cooled divertor operation) • H-mode ELM resolved (Standard and cooled divertor operation)
Pulse: Coordinate with Ex 2.2.1 Determination and control of the intrinsic impurity composition in the full W divertor Ex 2.1.3 Characterization of the L-Mode domain Ex 3.1.2 Characterisation of detached plasmas .... Based on reference Pulse Ex 1.1.2 HT3 R/L VHi5_4M5_LT Dens3 Dens2 Dens1 First Session: Lmode Consistency check of Spectroscopy Diagnostics Tungsten and Impurity Lines – Settings and Limits Initial estimation of Tungsten and Impurity behavior/impact
Toconsider • ~ 10 Pulses • Use KT3 A,B,C (check for >500nm) • Use KL11 2 Red (>505) / 2 Blue Cameras (505) • KS3 PMT (Da,WI,C, BeII) • KS3A (420-620 nm) • KS3B Highres (ggf compare with PMT - WI) • KS8 redirected Configuration HT/LT A Check if something changes – else dont use 6 Wavelengthrangesfor KT3A (UV- ???) Power changes 1.2 vs 3 MW ? B Check if something changes – else dont use 1 Pulse: 2 Pulse: 3rd Pulse potential repeat .... Divertor Gas (Gim9/Gim11) C
Wavelength KS3A,B,C 5 sets min. 2 Pulses Typical UV 1 248.9 WII, 255 WI, 257 WII, 261 WI- important for planck backround - refelections UV2 361.38 WII, 361.75 WI, 363.2 WI, 364.14 WII, 364.56 WII - check for direkt comp. WI/WII Vis1 397(Depsilon), 399.5 NII, 400.9 WI,402.5 FII, 410 Ddelta - main used line incl. Hydrogen Lines Vis2 426.7 CII, 429.46 WI, 431 CD, 434.81 WII, Dgamma 435.7 O, 436 BeII - std. impurities Vis3 500.5 NII, 505.3 WI 5145 CII 5165 C2 522.7 WI Keep one as standard window Use WI vs WII for prompt redeposition
Other Settings KL11 1st Pulse 400.8, 505.32 WI Blue Cameras (<510 nm) 522.47 WI, 656 Da Red Cameras 2nd Pulse 400.8 WI 465 CIII, Blue Cameras (<510 nm) 527 Be II, 656 Da Red Cameras Use for localization of WI and Imp. Change toseededimp. whenuses KS8 (all shots) Redirect to Divertor Use for whole high-res Wavelength range (~ 300-700nm) KS3 B (High Res) 400.8 WI 429 505. WI,522 WI line structure (Zeeman etc) (for comp with KS3 PMT, checking of KL11 filters)
Shotplan 1st Session L-Mode Setup Pulse & 1 flattop pulse (check effect of Tile Temp) 1(2) pulses HT3R IF OK 2 Repetitions for KT3 A,B,C (repeat if saturated etc) VHi5 IF OK 2 Repetitions for KT3 A,B,C (repeat if saturated etc) 2+2(3+3) pulses - - - - - - pick one Scenario test gim11 vs gim9 for divertor cooling 1 (2) pulses change NBI Power (1.2 MW <-> 3MW) 1 (2) pulses Configs will be used throughout campaign ---------------- 7 (12) pulses Minimum number of pulses requires full understanding of dynamic ranges for all diagnostics etc HT3L ?
+/- 1.5 cm 5 6 18 19 20 24 +/- 2 cm Diagnostics (initial List) Apart of Spectroscopy • Plasma charaterisation • KY4D: wall and edge probes • SOFT Xrays • CXRS • KV6 - QMBs • KL7 – overview IR • KL9A, KL9B, KL3B • thermocouples Divertor Langmuir-probes Divertor Thermocouples How to measure Core W?