Wave-Particle Interactions TSGWave-Particle Interactions TSGMid-Run AssessmentMid-Run Assessment

Gary TaylorGary Taylor

NSTXNSTX Supported by

NSTX Mid-Run Assessment MeetingJune 17, 2009

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College W&MColorado Sch MinesColumbia UComp-XGeneral AtomicsINELJohns Hopkins ULANLLLNLLodestarMITNova PhotonicsNew York UOld Dominion UORNLPPPLPSIPrinceton UPurdue USNLThink Tank, Inc.UC DavisUC IrvineUCLAUCSDU ColoradoU MarylandU RochesterU WashingtonU Wisconsin

Culham Sci CtrU St. Andrews

York UChubu UFukui U

Hiroshima UHyogo UKyoto U

Kyushu UKyushu Tokai U

NIFSNiigata UU Tokyo

JAEAHebrew UIoffe Inst

RRC Kurchatov InstTRINITI

KBSIKAIST

POSTECHASIPP

ENEA, FrascatiCEA, Cadarache

IPP, JülichIPP, Garching

ASCR, Czech RepU Quebec

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 2

OverviewOverview

• Three EP 1Three EP 1stst tier XP’s run so far tier XP’s run so far– XP-905: “Current Profile Modifications and Fast Ion Loss from XP-905: “Current Profile Modifications and Fast Ion Loss from

BAAEs/EPMs” (Darrow)BAAEs/EPMs” (Darrow)

– XP-916: “Study of TAE-Induced Fast Ion Transport in L-Mode XP-916: “Study of TAE-Induced Fast Ion Transport in L-Mode Plasmas” (Podesta/Crocker/Fu) Plasmas” (Podesta/Crocker/Fu) [Awaiting HHFW to complete][Awaiting HHFW to complete]

– XP-917: “FIDA Blue/Red Checkout” (Heidbrink/Podesta)XP-917: “FIDA Blue/Red Checkout” (Heidbrink/Podesta)

• Three HHFW & One EP 1Three HHFW & One EP 1stst tier XP’s (5 run days) tier XP’s (5 run days) awaiting availability of HHFW Systemawaiting availability of HHFW System

• Three EP 2Three EP 2ndnd tier XP’s (1.5 run days) tier XP’s (1.5 run days)

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 3

Status of XP ResultsStatus of XP Results

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-905: Current Profile Modifications and Fast Ion Loss from BAAEs/EPMs

Goals:

• Generate BAAE/EPM bursts during steady Ip phase of discharge, widely separated enough in time to allow good MSE measurements of the current profile before and after the bursts

• Measure fast ion loss pitch angle and energy distributions

• Measure effects on confined beam ions

• Measure internal mode structure

• Apply n=3 braking to get modes with no flow shear & compare with NOVA modeling

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-905: BAAEs/EPMs Have No Greater Effect on j(r) than General MHD in NSTX

Results:

• Modes obtained under 2 conditions

• Good time separation for MSE in 1 case

• Density low enough for good FIDA data in other case

• Good reflectometer data obtained for fitting to NOVA eigenfunctions

• Good fast ion loss data obtained

• n=3 braking work incomplete

• Modes have no greater effect on j(r) than general MHD

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-916: TAEs Studies in L-mode, Center-Stack Limited Deuterium Plasmas - Summary of Day#1

• Good scenario with CS-limited, L-mode plasma achieved– Btor=5.5kG, Ip=0.9MA, n~3.2x1019m-3 @ 300ms

– TAEs and avalanches successfully reproduced

– Good diagnostic coverage

• Time window with frot≃0 through n=3 braking, ISPA~1kA – But: concerns about locked-modes. Avoid using SPAs in day#2?

• NB power scan (almost) completed for reference scenario– 1-2 shots at very low PNB (sources B&C @65kV) missing

• Toroidal field scan more difficult than expected– Hard to avoid low-f modes at 4.5kG, didn’t even try Btor=3.5kG

• Low-density shots missing (problems with glow system)

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

• Example : shot#132764

• TAEs + avalanches, t < 330ms

• TAEs only, t > 340ms

– SPAs ON, n=3 braking

• Interesting data on TAEs' decay and/or avalanches during NB notch

– Ex: 132748, 132761, 132764, ...

– Direct information on TAE damping?

shot# 132748

shot# 132764

NB ON

XP-916: Good Data on TAEs & Associated Fast IonTransport Collected for a Variety of Conditions

NB OFF

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-916: Plan for Day #2

1. Complete missing shots from day#1 NB power scan, very low NB power (2 shots) Quick NB power scan at low density (~4 shots)

2. Priority to shots for “code validation” & theory-experiment comparison

3. Electron temperature scan (requires HHFW, PRF~2MW)

4. NPA and f-FIDA scan, reference scenario

5. Elongation scan

Extended run day preferred...

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-917: FIDA Blue/Red Shift

Motivation: Resolve discrepancy between FIDA & FIDA simulation code in special quiet plasmas so we trust it for instability studies

Goal:

Vary fields to see if predicted spectral asymmetry associated with large gyroradius and large field line pitch is observed

Result: 13 good plasma shots at low beam power at BT(0) = 3.5, 4.5 and 5.5 kG & Ip = 0.5, 0.8, and 1.2 MA

Analysis status: Completed simulations--comparison with data in progress

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009

XP-917: Poor Agreement Still Observed BetweenTheory and Experiment

• Would greatly benefit from reversed field (BT and/or Ip) comparison shots!

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WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 11

Remaining 1Remaining 1stst & 2 & 2ndnd Tier XPs Tier XPs

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 12

Remaining 1Remaining 1stst Tier WPI TSG XPs Require 5 Run Days Tier WPI TSG XPs Require 5 Run Days

• XP-944: “ HHFW Heating & Edge Effects in L-Mode” (Ryan/Hosea)– Run after 2-4 run days of XMP-26 HHFW plasma conditioningRun after 2-4 run days of XMP-26 HHFW plasma conditioning– Lithium conditioning at ~ 20 mg/minLithium conditioning at ~ 20 mg/min– Requires 1.5 run daysRequires 1.5 run days

• XP-946: “ HHFW Heating & Edge Effects in H-Mode” (Ryan/Hosea)– Lithium conditioning at ~ 20 mg/minLithium conditioning at ~ 20 mg/min– Run after XP-944Run after XP-944– Requires 1.5 run daysRequires 1.5 run days

• XP-920: “HHFW Heating of Low TXP-920: “HHFW Heating of Low Tee(0), I(0), Ipp Plasmas” (Taylor) Plasmas” (Taylor)– Lithium conditioning at ~ 20 mg/minLithium conditioning at ~ 20 mg/min– Run after XP-944 & XP-946Run after XP-944 & XP-946– Requires 1 run dayRequires 1 run day

• XP-916: “Study of TAE-Induced Fast Ion Transport in L-Mode Plasmas” “Study of TAE-Induced Fast Ion Transport in L-Mode Plasmas”

(Podesta/Crocker/Fu) (Podesta/Crocker/Fu) – Requires 1 (preferably extended) run day & ~ 2 MW of HHFWRequires 1 (preferably extended) run day & ~ 2 MW of HHFW

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 13

22ndnd Tier WPI TSG XPs Require 1.5 Run Days Tier WPI TSG XPs Require 1.5 Run Days

• XP-906: “ Development of H-Mode TAE Avalanche Target Plasmas” (Fredrickson)– 2008 candidate shots identified, explore parameters for TAE avalanches2008 candidate shots identified, explore parameters for TAE avalanches– Requires 0.5 run daysRequires 0.5 run days

• XP-907: “ Documentation of CAEs & GAEs” (Fredrickson/Gorelenkov)– Requires 0.5 run daysRequires 0.5 run days– Attempt to reproduce previous “Angelfish” shotsAttempt to reproduce previous “Angelfish” shots

• XP-947: “HHFW Modification of Rapidly-Chirping Beam-Driven XP-947: “HHFW Modification of Rapidly-Chirping Beam-Driven

Instabilities” (Heidbrink)Instabilities” (Heidbrink)– Needs > 2 MW, 30 ms pulses of HHFW Needs > 2 MW, 30 ms pulses of HHFW – Start with previous “Angelfish” shots, BStart with previous “Angelfish” shots, BTT(0) ~ 4 kG L-mode(0) ~ 4 kG L-mode– Requires 0.5 run dayRequires 0.5 run days

WPI TSG Mid-Run Assessment (Taylor) June 17, 2009 14

XPs Run with Reversed BXPs Run with Reversed BTT Require 1 Run Day Require 1 Run Day

• XP-944: “ HHFW Heating & Edge Effects in L-Mode” (Ryan/Hosea)

– Antenna phase scan Antenna phase scan (-150o, -90o, -30o and +90o)

– Current scan from 0.7 to 0.9 MA with -90o phasing

– Requires 0.5 run daysRequires 0.5 run days

• XP-917: “FIDA Blue/Red Checkout” (Heidbrink/Podesta)XP-917: “FIDA Blue/Red Checkout” (Heidbrink/Podesta)

– Scan BScan BTT(0) from 3.5 to 5.5 kG & I(0) from 3.5 to 5.5 kG & Ipp from 0.5 to 1.2 MA from 0.5 to 1.2 MA

– Requires 0.5 run days (can limit BRequires 0.5 run days (can limit BTT(0) & I(0) & Ipp scans if less time available) scans if less time available)