(MAP) Session Report
Date: Apr. 18, 2024
Time: 12:25 – 16:43
Shot#: 189830 – 189898 (69 shots)
Prior wall conditioning: H2 glow
Divertor pump: ONGas puff: H2
Pellet: Si, W, Cu, Ti, Mo

Apr. 19, 2024 (C. Suzuki)

NBI#(1, 2, 3, 4, 5) = gas(H, H, H, H, H)=P(4.6, 4.5, 4.3, 3.7, 2.7) MW
ECH(77GHz) = ant(1.5-Uo, 5.5-U, 2-OUR)=P(-, 0.70, 0.38) MW
ECH(154GHz) = ant(2-OLL, 2-OUL, 2-OLR)=P(0.71, 0.89, 0.98) MW
ICH(3.5U, 3.5L, 4.5U, 4.5L) = P(-, -, -, -) MWTopics
1. Calibration of Solar EUV Spectrometers and Validation of Diagnostic Capability for Solar High- Temperature
Plasmas by LHD Experiments (H. Hara (NAOJ), I. Murakami)
2. Transport analysis of heavy impurity ions in core plasma (S. Satake)
3. Study of the impact of turbulence reduction via boron injection on impurity confinement and transport (D. M.
Roque (Ciemat), N. Tamura)Si TESPEL Injection for emission line diagnostics
H. Hara, Murakami, I., Kato, D., C. Suzuki, T. Kawate, N. Tamura et al.

Objectives:• Validation of plasma diagnostic capability
by Si emission line ratios for studying
the solar corona

Experimental Conditions:• H gas, Rax=3.9m, Bt=-1T, 𝛾=1.254, Bq=100• Si contained TESPEL injection at 3.95 sec• #189831-#189840 (10 shots)＊SiN contained TESPEL injections executed# 189838 (2024)
t =4.0-4.8 [s]Results:• We have detected target Si X lines with Si VII,
Si VIII, Si IX, and Si XI lines.

Ne• These are to be used for the on-orbit
spectrometer calibration by branching lines andplasma diagnosis by density-sensitive line pairsof Si and other elements.
Si IX
225.02 227.00
227.36Si X

Si VIII

256.38 261.06
branching lines
He II
271.99 277.26
256.38253.79258.37277.06

TeSi XI

Si XI

303.33

He II

303.78branching lines# 189838 (2024)
t =4.0-4.8 [s]358.64349.87365.41361.40 371.49

364.502024/4/18 “Transport analysis of heavy impurity ions in core plasma” S. Satake (NIFS)
Objective of the experiment
Before LHD shutdown, obtain the experiment data ofplasma with W impurity so that we can analyze thetransport process of heavy impurity species in the future.
Operation• Plasma : Rax=3.75, Bax=2.64, γ＝1.2538 , CW
• Pellet : W 0.1φ x 0.7, C 0.7φ-0.25φ (5~7 × 1017 Watoms)• Diagnostics : HIBP (core-Er), Visible & EUV
spectrometers (W impurity profile)
••

•
•

•

W pellet was injected and tangential NBIs turned on
at t=3.9
Without NBI#1, ne peaking was observed(𝑛𝑛𝑒𝑒 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 ∼ 5𝑒𝑒𝑒𝑒) and then suddenly began todecrease from t=4.6s.
𝑇𝑇𝑇𝑇 dropped from 1.5 to 0.5keV end increased again asne decreases.
From 𝑛𝑛𝑒𝑒 profile & radiation power, W appears to haveaccumulated in the center once and then turned toexhale.
Precise W profile from spectrometer will be analyzed
later.

(1)

2024/4/18 “Transport analysis of heavy impurity ions in core plasma” S. Satake (NIFS)
••

•

•

•

When NBI#1 was added , core 𝑛𝑛𝑒𝑒 did not increased somuch (𝑛𝑛𝑒𝑒 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 ∼ 3𝑒𝑒𝑒𝑒). Strong NBI heating seemed toprevent the accumulation of pellet-oriented electrons tothe plasma center (and probably W, too).
Note that n&T profiles @ t=3.9 – 4.1 s was similar to theshot w/o NBI#1. Difference appeared b/w two shots
appeared from t=4.1.
𝑛𝑛𝑒𝑒 profile became very peaky @ t=4.3, where hollow-𝑇𝑇𝑒𝑒
was also observed. Probably core 𝑇𝑇𝑒𝑒 was dropped
because of radiation loss by W which was accumulatedaround the magnetic axis. Ti was about 2.0keV at thecenter, which was slightly higher (1.5keV) in the shotw/o NBI#1.
Soon after peaked-𝑛𝑛𝑒𝑒 profile was formed, 𝑛𝑛𝑒𝑒 began to
decay and 𝑇𝑇𝑒𝑒 increased.
There is a delay between the start timing of 𝑛𝑛𝑒𝑒 drop
(t=4.2s) and radiation drop (t=4.4s).  reflect thedifference in the radial flux of electron and tungsten?

(2)

Study of the impact of turbulence reduction via boron (lithium) injection on impurity
confinement and transport (D. Medina Roque, N. Tamura, I. García Cortés, K. J. McCarthy, F. Nespoli et al.)Magnetic configuration: (Rax, Polarity, Bt, γ, Bq) = (3,6 m, CW, 2.75 T, 1.2538, 100.0%)
Shots: #189879 - #189898
Goal of this experimentl Characterize Z-Dependence of the impurity confinement and transport with TESPEL injections in the turbulence-reduced
phase during the Li injection with the IPD.
l Obtain data for comparisons with future results in W7-X and TJ-II.
Background & Motivationl In Nespoli Nat. Phys 2022 it was shown that significant B injection with the IPD triggers a turbulence-reduced andconfinement-improved phase. But an study of the behavior of the impurities in this scenario remains outstanding. This isof great interest, since when the turbulence level is strongly reduced, neoclassical impurity transport could be of higher
importance and the Z-Dependence of impurity transport should be observed.
ü Estimate an impurity decay time from the line intensity evolution for injected elements (Ti, Cu, and Mo) for plasmas
w/ and w/o impurity hole using EUV/VUV spectrometer SOXMOS (its wavelength range from 19.7 to 34.1 nm with a133.6 g/mm grating for Ti, from 14.5 to 27.4 nm with a 133.6 g/mm for Cu, and from 8.9 to 13.2 nm with a 600 g/mm
grating for Mo).

Study of the impact of turbulence reduction via boron (lithium) injection on impurity
confinement and transport (D. Medina Roque, N. Tamura, I. García Cortés, K. J. McCarthy, F. Nespoli et al.)l We obtained data for all impurities w/ and w/o IPD
Resultsl 15 TESPELs are successfully injected at 5.225s (8 into w/ IPD) plasmas.
l Impurity confinement time from SOXMOS signals Erand (7 into w/o IPD) at 3.8-6.8s while keeping ne at 5e19 m-3
from CXRS and DR and turbulence level from PCI andHeating pattern
DR will be analyzed.
ECH#1,2,4,5,7(3s-5s) NB#1(3.3s-5s)(t), NB#2,3(5s-7s)(t), NB#4(5sl No impurity accumulation is preliminarily from ne and Te
7s)(p)(80 on/20 off), NB#5(5s-7s)(p)(20 on/80 off)
Typ waveforms
Ti
CuMo
IPD (189891) w/o IPD (189893) IPD (189884) w/o IPD (189887) IPD (189894) w/o IPD (189896)

E
DIP ESP
TL
TE

E
SPL