Overview of JT-60U Results for Development of Steady-State Advanced Tokamak Scenario

H. Takenaga 1) and the JT-60 Team

21st IAEA Fusion Energy Conference16 - 21 October 2006

Chengdu, China

OV/1-2

1) Japan Atomic Energy Agency

1997

Enhanced national and international collaborations.

National collaborations : as the central tokamak in Japanese fusion research.

International collaborations : including IEA/ITPA c ollaboration.

The JT-60 TeamJT-60U

N.Aiba1), H.Akasaka, N.Akino, T.Ando3), K.Anno, T.Arai, N.Asakura, N.Ashikawa4), H.Azechi5), M.Azumi, L.Bruskin6), S.Chiba, T.Cho7), B.J.Ding8), N.Ebisawa, T.Fujii, K.Fujimoto1), T.Fujita, T.Fukuda5), M.Fukumoto5), A.Fukuyama9), H.Funaba4), H.Furukawa2), M.Furukawa10), P.Gohil11), Y.Gotoh2), L.Grisham12), S.Haga2), K.Hamamatsu, T.Hamano2), K.Hanada13), M.Hanada, K.Hasegawa, H.Hashizume14), T.Hatae, A.Hatayama15), T.Hayashi2), N.Hayashi, T.Hayashi, H.Higaki7), S.Higashijima, U.Higashizono7), T.Hino16), T.Hiraishi17), S.Hiranai, Y.Hirano18), H.Hiratsuka, Y.Hirohata16), J.Hobirk19), M.Honda9), A.Honda, M.Honda, H.Horiike5), K.Hoshino, N.Hosogane, H.Hosoyama2), H.Ichige, M.Ichimura7), K.Ida4), S.Ide, T.Idehara20), H.Idei13), Y.Idomura, K.Igarashi2), S.Iio21), Y.Ikeda, T.Imai7), S.Inagaki4), A.Inoue2), D.Inoue7), M.Isaka, A.Isayama, S.Ishida, K.Ishii2), Y.Ishii, M.Ishikawa14), Y.Ishimoto1), K.Itami, T.Itoga14), Sanae Itoh13), Satoshi Itoh13), K.Iwasaki2), Y.Kagei1), S.Kajiyama22), S.Kakinoto7), M.Kamada1), Y.Kamada, A.Kaminaga, K.Kamiya, S.Kasai, K.Kashiwa, K.Katayama13), T.Kato4), M.Kawai, Y.Kawamata, Y.Kawano, T.Kawasaki13), H.Kawashima, M.Kazawa, K.Kikuchi2), H.Kikuchi2), M.Kikuchi, A.Kimura9), H.Kimura23), H.Kimura, Y.Kishimoto9), S.Kitamura, K.Kiyono, K.Kizu, N.Kobatake22), M.Kobayashi2), S.Kobayashi9), Y.Kobayashi9), T.Kobuchi4),K.Kodama, Y.Kogi13), Y.Koide, A.Kojima1), S.Kokubo17), S.Kokusen2), M.Komata, A.Komori4), T.Kondoh, S.Konishi9), S.Konoshima, S.Konovaliv24), A.Koyama9), M.Koyanagitsu23), T.Kubo5), H.Kubo, Y.Kudoh, R.Kurihara, K.Kurihara, G.Kurita, M.Kuriyama, Y.Kusama, N.Kusanagi2), J.Li24), J.Lonnroth25), T.Luce11), T.Maekawa9), K.Masaki,A.Mase13), M.Matsukawa, T.Matsumoto, M.Matsuoka26), Y.Matsuzawa2), H.Matumura2), T.Matunaga1), K.Meguro2), K.Mima5), O.Mitarai27), Y.Y.Miura5), Y.Miura, N.Miya, A.Miyamoto2), S.Miyamoto5), N.Miyato, H.Miyauchi23), Y.Miyo, K.Mogaki, Y.Morimoto23), S.Moriyama, M.Nagami, Y.Nagasaka22), K.Nagasaki9), Y.Nagase13), S.Nagaya,Y.Nagayama4), H.Naito28), O.Naito, T.Nakahata23), N.Nakajima4), Y.Nakamura4), K.Nakamura13), T.Nakano, Y.Nakashima7), M.Nakatsuka5), M.Nakazato2), Y.Narushima4),R.Nazikian12), H.Ninomiya, M.Nishikawa13), K.Nishimura4), N.Nishino29), T.Nishitani, T.Nishiyama, N.Noda4), K.Noto2), H.Nuga10), K.Oasa, T.Obuchi4), I.Ogawa20), Y.Ogawa10),H.Ogawa, T.Ohga3), N.Ohno17), K.Ohshima2), T.Oikawa, A.Oikawa, M.Okabayashi12), N.Okamoto17), K.Okano30), F.Okano, J.Okano, K.Okuno23), Y.Omori, A.Onoshi23), Y.Ono10), H.Oohara, T.Oshima, Y.Oya10), N.Oyama, T.Ozeki, V.Parail25), H.Parchamy4), B.J.Peterson4), G.D.Porter31), A.Sagara4), G.Saibene32), T.Saito7), M.Sakamoto13),Y.Sakamoto, A.Sakasai, S.Sakata, T.Sakuma2), S.Sakurai, T.Sasajima, M.Sasao14), F.Sato2), M.Sato, K.Sawada33), M.Sawahata, M.Seimiya, M.Seki, J.P.Sharpe34),T.Shibahara17), K.Shibata2), T.Shibata, T.Shiina, R.Shimada21), K.Shimada, A.Shimizu13), K.Shimizu, M.Shimizu, K.Shimomura21), M.Shimono, K.Shinohara, S.Shinozaki, S.Shiraiwa10), M.Shitomi, S.Sudo4), M.Sueoka, A.Sugawara2), T.Sugie, K.Sugiyama17), A.M.Sukegawa, H.Sunaoshi, Masaei Suzuki2), Mitsuhiro Suzuki2), Yutaka Suzuki2), S.Suzuki, Yoshio Suzuki, T.Suzuki, M.Takahashi2), R.Takahashi2), K.Takahashi2), S.Takamura17), S.Takano2), Y.Takase10), M.Takechi, N.Takei, T.Takeishi13), H.Takenaga, T.Takenouchi2), T.Takizuka, H.Tamai, N.Tamura4), T.Tanabe13), Y.Tanai2), S.Tanaka9), J.Tanaka9), S.Tanaka10), T.Tani, K.Tani, H.Terakado2), M.Terakado, T.Terakado, K.Toi4),S.Tokuda, T.Totsuka, Y.Toudo4), N.Tsubota2), K.Tsuchiya, Y.Tsukahara, K.Tsutsumi2), K.Tsuzuki, T.Tuda, T.Uda4), Y.Ueda5), T.Uehara2), K.Uehara, Y.Ueno9), Y.Uesugi35),N.Umeda, H.Urano, K.Urata2), M.Ushigome10), K.Usui, K.Wada2), M.Wade11), K.Watanabe4), T.Watari4), M.Yagi13), Y.Yagi18), H.Yagisawa2), J.Yagyu, H.Yamada4), Y.Yamamoto9), T.Yamamoto, Y.Yamashita2), H.Yamazaki2), K.Yamazaki4), K.Yatsu7), K.Yokokura, I.Yonekawa3), M.Yoshida1), H.Yoshida5), N.Yoshida13), M.Yoshida13), H.Yoshida16), H.Yoshida, A.Yoshikawa23), M.Yoshinuma4), H.Zushi13)

Japan Atomic Energy Agency, 1)Post-Doctoral Fellow, 2)Staff on loan, 3)Nippon Advanced Technology Co.Ltd., Japan

8)Southwestern Institute of Physics, China, 11)General Atomics, USA, 12)Princeton Plasma Physics Laboratory, USA, 19)Max-Planck-Institut fur Plasmaphysik, Germany, 24)JAERI Fellow, 25)Euratom/UKAEA Association, UK, 31)Lawrence Livermore National Laboratory, USA, 32)EFDA Closed Support Unit, Germany, 34)Idaho National Engineering and Environmental Laboratory, USA

4)National Institute for Fusion Science, Japan, 5)Osaka University, Japan, 6)Japan Society of the Promotion of Science Invitation Fellowship, 7)University of Tsukuba, Japan, 9)Kyoto University, Japan, 10)The University of Tokyo, Japan, 13)Kyushu University, Japan, 14)Tohoku University, Japan, 15)Keio University, Japan, 16)Hokkaido University, Japan, 17)Nagoya University, Japan, 18)National Institute of Advanced Industrial Science and Technology, Japan, 20)Fukui University, Japan, 21)Tokyo Institute of Technology, Japan, 22)Hiroshima Insitute of Technology, Japan, 23)Shizuoka University, Japan, 26)Mie University, Japan, 27)Kyushu Tokai University, Japan, 28)Yamaguchi University, Japan, 29)Hiroshima University, Japan, 30)Central Research Institute of Electric Power Industry, Japan, 33)Shinshu University, Japan, 35)Kanazawa University, Japan

0 1

Saf

ety

fact

or

r/a

Strong p(r) and q(r) linkage among physics with variou s time scales

Transport

MHD stability

Current diffusion

Bootstrap current Plasma WallInteraction

HeatingRotation controlCurrent driveFuelling

JT-60U objectives and strategy

� ITER Physics R&D� Advanced Tokamak (AT) Concepts for ITER & DEMO

AT plasmas : high ββββN & high bootstrap current fraction (f BS)� high ββββp mode plasma

JT-60U

0 1

Pre

ssur

e

ITB

weakstrong

r/a

ETB

� reversed shear (RS) plasma

� Sustainment of high ββββN below no wall ideal limit and high f BSlonger than the current diffusion time.

� High ββββN exceeding no wall ideal limit.� Integrated performance in the long high ββββN discharges.� Development of real time control systems towards inte lligent control

for the high f BS plasmas.

'05-'06

'03-'04Main topics

Schematic view of research area in ββββN-fBS spaceJT-60U

Ferritic Steel Tiles (FSTs) are installed inside the vacuum vessel to reduce toroidal field ripple.

� Decrease in fast ion loss with the large volume configuration close to the wall, where wall stabilization effectively w orks.

β N

DEMO

JT-60SA

ITER-SS

ITER-Hybrid

ITER-Inductive

NTM

RWM

fBSp(r) & q(r) linkage

No wall limit

Ideal wall limit

High ββββN exceeding no wall limit– Wall stabilization effect– Suppression of resistive wall mode

(RWM) by plasma rotation

Integrated performance– Confinement improvement– Robustness for current profile diffusion– Effect of plasma wall interaction

Real-time control systems– Pressure profile control– Real-time current profile control

0

1

2

3

4

5

0 20 40 60 80 100

Contents

1. Installation of ferritic steel tiles and its effe cts in L- and H-mode plasmas

2. Extension of operation regime to high ββββN exceeding no wall ideal limit and RWM study

3. Integration of plasma performance in the long high ββββNdischarges

4. Development of real time control with high bootst rap current fraction

5. Physics studies on issues implicated for ITER

6. Summary

JT-60U

1. Installation of ferritic steel tiles and its eff ects in L- and H-mode plasmas.

� FSTs cover ~10% of the surface.

� Large effect is obtained at BT < ~2 T.

� 3-D Monte-Carlo simulations (F3D OFMC) for fast ion be havior indicated that total NB absorbed power is increased by 30% (by 50% for perpendicular NB) in the large volume configuration.

K. Shinohara (FT/P5-32, Thu.)

FSTs

0.0

20.0

40.0

60.0

80.0

100.0

total perp. co ctr co

w/o FSTs w FSTs

Abs

orbe

d po

wer

(%

)

P-NB N-NB

Ip = 1.1 MA, BT = 1.86 T, VP= 79 m3quasi-ripple well

region

w FSTs

w/o FSTs

JT-60U

The present

Spin -up of toroidal rotation in co -direction due to

reduction of fast ion loss.

Ripple trapped loss

F3D OFMC calculation< 0.3 MW/m2 w FSTs> 1 MW/m2 w/o FSTs

< 0.2 MW/m2

� Heat flux in the ripple trapped loss region measured with IRTV i s consistent with that calculated by F3D OFMC .

� Toroidal rotation shifts to co-direction due to the reduction of the fast ion loss.

K. Shinohara (FT/P5-32, Thu.) M. Yoshida (EX/P3-22, Wed.)

JT-60U

Ip = 1.2 MA, BT = 2.6 T,q95 = 4.1, Vp = 75 m3, L-mode

-50

0

50

100

150

0 0.2 0.4 0.6 0.8 1

VT

(km

/s)

r/a

w/o FSTs

w FSTs

1u perp. & 2u co-NB

w FSTs

w FSTs

w/o FSTs�

Pedestal parameters and confinement are enhanced with co-rotation in H-mode.

� Ip = 1.2 MA, BT = 2.6 T, q95 = 4.1, Vp = 75 m3

� Pedestal pressure increases with the increase in toroidal rotation at the pedestal in co-direction .

� Energy confinement is improved by enhancing core toroidal rotation in co-direction .

� Pedestal pressure and confinement are raised with FSTs e ven at a given toroidal rotation.

H. Urano (EX/5-1, Thu.)

0.7

0.8

0.9

1

1.1

-300 -200 -100 0 100 200

HH

98(y

,2)

VT(r/a=0.2) (km/s)

2

4

5

6

7

-100 -50 0 50VT

ped (km/s)

Ppe

d(k

Pa)

JT-60U

3

ctr-

bal- co-NBw FSTs

w/o FSTsctr- bal-co-NB

ctr-

bal-

co-NBw FSTs

w/o FSTsctr-

bal-co-

2. Extension of operation regime to High ββββNexceeding no wall ideal limit and RWM study

• Suppression of RWM by plasma rotation is a key.• Estimation of critical rotation velocity for suppressing RWM is

important.

β N

DEMO

JT-60SA

ITER-SS

ITER-Hybrid

ITER-Inductive

NTM

RWM

fBSp(r) & q(r) linkage

No wall limit

Ideal wall limit

0

1

2

3

4

5

0 20 40 60 80 100

0

1

2

3

4

5

0.8 0.9 1 1.1 1.2 1.3 1.4

ββββN reaches ideal wall limit.

M. Takechi (EX/7-1Rb, Fri.)

� High ββββp ELMy H-mode plasma : BT=1.58 T, Ip=0.9 MA, δ0~20 cm (d/a=1.2)� Increase in net heating power due to the FSTs install ation allows to

access high ββββN up to 4.2 with l i=0.8-1. � n=1 mode at high beta region.� Growth time of 1/ γγγγ~1 ms (< ττττw~10 ms) before collapse.� RWM is suppressed by plasma rotation (100km/s at r/a=0 .3).

li

β N

Vp>70 m3βN=5xliβN=4xli βN=3xli

JT-60U

ideal wall limit

no wall limit

1/γγγγ~1ms

w FSTs

w/o FSTsafter 20th IAEA

before 20th IAEA

-0.01

0

0.01

6.5 6.55 6.6 6.65 6.7Time (s)

3

3.5

4

-0.01

0

0.01

6.64 6.645 6.65 6.655 6.66Time (s)

ββ ββ NB

(a.

u.)

~B

(a.

u.)

~

li~0.9E045480

05

1015

5.5 6 6.5 7Time(s)

0

5

0

5

05

10152025

-100

-50

02

2.5

3

Small critical rotation velocity of V C/VA~0.3% is found at q95=3.5 for suppressing RWM.

JT-60U� Less counter rotation due to the FSTs installation enables to change the

rotation in co-direction close to zero.

β NV

T(k

m/s

)B

(G

)~

PN

Bct

r

(MW

)P

NB

co

(MW

)P

NB

perp

(MW

)

ctr

co

M. Takechi (EX/7-1Rb, Fri.)

no wall ideal limit

� VC~15 km/s� Growth time of 1/ γγγγ~10 ms (~ ττττW) � No increase in V C for higher C ββββ.� Large impact on ITER & DEMO.

no wall limit

(βN

-β N

no_w

all )

(βN

idea

l_w

all-

β Nno

_wal

l )C

β=

at q=2

E046710E046743

G. Matsunaga (EPS 2006)

-0.2

0

0.2

0.4

0.6

0.8

1

-100 -50 0 50V

T (km/s)

ideal wall limit

switch from ctr-to co-NB

3. Integration of plasma performance in the long high ββββN discharges.

• Confinement improvement is a key.• Robustness for current profile diffusion should be dem onstrated.• Change of wall pumping with a long time scale is im portant issue.

β N

DEMO

JT-60SA

ITER-SS

ITER-Hybrid

ITER-Inductive

NTM

RWM

fBSp(r) & q(r) linkage

No wall limit

Ideal wall limit

0

1

2

3

4

5

0 20 40 60 80 100

High ββββNHH98(y,2)=2.2 is sustained for 23.1 s (~12 ττττR) with fBS=36-45% at q95~3.3.

• High ββββp ELMy H-mode plasmas : Ip = 0.9 MA, BT = 1.6 T, Vp = 67 m3

• Increase in net heating power due to the FSTs install ation allows flexible combination of NB units. ���� peaked heating profile and co-injection.

• Density increase degrades confinement in the latter ph ase.

N. Oyama (EX/1-3, Mon.)

0 5 10 15 20 25 30 35Time (s)

0

3

12

1

0.5

0

0123

151050

4

2

0

I p(M

A)

β N,

HH

98(y

,2)

n e(1

019m

-3)

PN

BI(M

W)

I Dα

(a.u

.)

βN

HH98(y,2)

JT-60U

τR=µ0<σ>a2/12 : D.R. Mikkelsen, Phys. Fluids B 1(1989) 333.

ITERBaseline

ITERHybrid

β NH

H98

(y,2

) after 20th IAEAw FSTs

before 20th IAEA, w/o FSTs

.

1

1.5

2

2.5

3

0 5 10 15 20 25 30 35Sustained duration (s)

r/a

0

10

20

30

40

50

0

1

2

3

4

5

-60-40-20

020

4060

0 0.2 0.4 0.6 0.8 1

Pth

(kP

a)

q

VT

(km

/s)

w FSTs

w FSTs

w/o FSTs

w/o FSTs

ITER-SS(I)ITER-hybrid (A C C Sips, et al., PPCF 47 (2005) A19.)w FSTs (45436@18s)w/o FSTs (44092@15s)

HH98(y,2)βN

fBS

fCD

Fuel purity

Prad/Pheat

ne/nGW

0.56

0.83

1.32.56

0.5

1

0.77

Density is successfully controlled by divertor pumping in enhanced recycling region.

H. Kubo (EX/P4-11, Thu.)

1018 1019 10201020

1021

1022

Fuelling ofPNB~10 MW

Div

erto

r pu

mpi

ng (

/s)

IDααααdiv (a.u.)

δδδδ=0.3

δδδδ=0.24

JT-60U

0 0

0

Wdi

a(M

J)n

e(1

019m

-3)

PN

B(M

W)

0

2

0

10

-0.5ΦΦ ΦΦ

(1022

s-1) 0

ΦΦ ΦΦ(1

022s-1

)

I Dαα αα

(1021

s-1)

1

4

200400

600

0 5 10 15 20 25 30Time (s)

T( °° °°C

)

Divertor-plate temperature

NBIDivGas

E045334

Wall-pumping rate

4

1.5

2.5

800

8

20

� The outgas could be attributed to increase in divertor plate temperature.

� HH98(y,2) ~ 0.71 at 0.64nGW.� High confinement at high

density is remaining issue.

Ip = 1.2 MA, BT = 2.2 T, q95 = 3.6

wall pumping

� Divertor pumping depends on recycling .

4. Development of real time control with high boots trap current fraction

� Understanding of p(r) and q(r) linkage.� Current profile control is important for AT plasmas.

p(r) q(r)

V(r)

MSELH

Fast-CXRSco- & ctr-NB

Fast-CXRSECEOn & off-axis NB

detectoractuator

β N

DEMO

JT-60SA

ITER-SS

ITER-Hybrid

ITER-Inductive

NTM

RWM

fBSp(r) & q(r) linkage

No wall limit

Ideal wall limit

0

1

2

3

4

5

0 20 40 60 80 100

6.8 s7.6 s

High f BS of 70% is sustained for 8 s by p(r) control at qmin= 4 with real time q min estimation.

Y. Sakamoto (EX/P1-10, Tue.)

00.20.40.60.8

-0.500.51

I p(M

A)

Vlo

op(V

)

00.5

11.5

051015

02468

10

0246810

0123

0

5

1

4 6 8 10 12 14Time (s)

PN

B(M

W)

Te

(keV

)I D

α(a

.u.)

β NT

i(k

eV)

n e(1

019

m-3

)

JT-60U

ctr-NB

q min

345

2

4

6

8

10

12

0 0.2 0.4 0.6 0.8 1

6.8 s8.3 s

q

r/a

02468

-500

50100150

0.4 0.6 0.8r/a

Ti(k

eV)

VT

(km

/s)

qmin=4

Wdia control by NB

� RS plasma : q 95~8.5, HH98(y,2)~1.8, ββββN~1.4.� Ctr-NB off for p(r) control at q min=4 for 1.0s.

� j(r) approaches SS, while, n e(r) still evolves for ττττ> ττττp*(~2s) and plasma collapses.�p(r) control is important even with nearly SS

j(r) and q min being not integer.

MSE

co- & ctr-NB

2

4

6

8

10

1208.3s09.3s10.3s11.3s12.3s13.3sq

-0.1-0.05

00.05

0.10.15

5.8 - 6.8 s8.3 - 10.3 s11.8 - 13.3 s

Vlo

op (

V)

012345

0 0.2 0.4 0.6 0.8 1

t=10.3 st=13.3 s

n e (10

19 m

-3)

r/a

E045903

Real time q min control demonstrated with MSE diagnostics and LHCD at f BS=0.46.

• Reduction of fast ion loss due to the FSTs installa tion increases compatibility of LHCD with high power heating.

• qmin control is affected by dynamic behavior related to the strong linkage of p(r) and q(r) .

T. Suzuki (EX/6-4, Thu.)

JT-60U

qMSE qmin qmin,ref

∆∆∆∆PLH

LHMSE

Real time q min control scheme

0

10

20

0

0.8

1.6

0

0.5

1.0

1.5

1

1.5

2

7 8 9 10 11 12 13 14 15Time (s)

q min

PLH

(MW

)P

NB

(MW

)

β N

ref.

command

02468

Te

(keV

)

MSELH

� Transport reduction at t=12.4 s

� Time delay in response of qmin

jOH or jBSchange

r/a~0.20.4

0.6

Control for bootstrap sustained plasma (f BS~100%) is challenging.

Y. Takase (EX/1-4, Mon.)

� Bootstrap sustained plasma can reduce center solenoid (CS) coil capability, which has a large impact on the economic aspect.

� Nearly constant current (~0.54 MA) is maintained by B S current with constant I CS and negative NBCD current for ~1 second.

� Both W dia and Ip gradually decrease in the strong linkage even with con stant Wdia control.

0.6

01.5

04.5

020

01

03 4 5 6Time (s)

5

-525

04

0-2

-46

0V

loop

(V)

PN

B(M

W)

β pI C

S(k

A)

Sn

(1014

s-1)

I p(M

A)

Wdi

a(M

J)β N

n e(1

019m

-3)

I VT, I

VR

(kA

)I D

α(a

.u.)

βNWdia

IVTIVR

E046687

JT-60U

BT = 4 T, βN=1.15ICS constantWdia constant FB

5. Physics studies on issues implicated for ITER.

�NTM suppression by ECCDJEC/JBSDependence of EC deposition positionModeling

• Behavior of energetic ions with Alfvén eigenmodesNeutron emission profile measurementsComparison with classical calculation

• ELM propagation in SOL plasmaMeasurements with multi reciprocating probes (LFS and H FS)

JT-60U

2/1 NTM is suppressed at J EC=0.5JBS with well aligned ECCD to q=2 surface.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

0.4 0.5 0.6 0.7ρρρρEC

B0.5TOPICS

Island

~W(1

1.5s

) / W

(9.5

s)

• 2/1 NTM is destabilized with the misalignment compa rable to the island width .

• TOPICS simulation well reproduces the experimental resu lts with the same set of coefficients of the modified Rutherford equation.

A. Isayama (EX/4-1Ra, Thu.)

EC0

1

2

3

B (

a.u.

)~

EC0

1

2

3

EC

139 10 11 12time [s]

0

1

2

3

B (

a.u.

)~

B (

a.u.

)~

ρρρρEC=0.62

ρρρρEC=0.60

ρρρρEC=0.44

JT-60U

0.5Wisland<∆ρ<Wisland

∆ρ~0.5Wisland

∆ρ>Wisland

(A)

(B)

(C)

(A)

(B)(C)

∆ρ=|ρEC-ρisland-center|

Energetic ions are transported from core region due to AEs with moderate amplitude.

JT-60U

• Understanding of the alpha particle transport in the presence of AEs is one of the urgent research issues for ITER.

M. Ishikawa (EX/6-2, Thu.)

(A) with AEs (t=6.4s) (B) with weak AEs (t=7.8s)

� The measured neutron yield is significantly smaller than the classical calculation during AEs with moderate amplitude in the central region.

Neutron measurements

0

2

4

6

8

10

5 5.5 6 6.5 7 7.5 8neut

ron

coun

ts (

1013

m-2

s-1)

time (s)

-- r/a ~ 0.19 -- r/a ~ 0.32 -- r/a ~ 0.46 -- r/a ~ 0.56 -- r/a ~ 0.73 -- r/a ~ 0.84

NNB NNB

20

40

60

80

100

Fre

quen

cy (

kHz)

(A) (B)

0

2

4

6

8

10 MeasurementTOPICS

(1013

m-2s-1

)N

eutr

on fl

ux

0 0.2 0.4 0.6 0.8 1r/a

02468

101214 Measurement

TOPICS

(1013

m-2s-1

)N

eutr

on fl

ux

0 0.2 0.4 0.6 0.8 1r/a

Non-diffusive ELM propagation is observed in LFS SOL, but not in HFS SOL.

N. Asakura (EX/9-2, Fri.)

-0.5

0

0.5

0123

0 0.1 0.2 0.3time (ms)

0.4

-0.5

0

0.5

0246∆∆∆∆rmid =1.0cm

R (m) 2 3 4

-1

0

Z (

m)

SOL

SOL

Midplane Mach probe

X-point Mach probeHigh-field-side Mach probe

Target probe array (18 probes)

23cm

Probes and fast TV in JT-60U

∆∆∆∆rmid =0.8cm

HFS

LFS

JT-60U• Transient heat and particle load to the plasma

facing components (PFC) is a crucial issue.• Vperp

mid (peak)=0.4-1.2 km/s ( ∆∆∆∆rmid<5 cm), 1.5-3 km/s (∆∆∆∆rmid>6 cm)

j sHF

S

(105

Am

-2)

B (

a.u.

)j sLF

S

(105

Am

-2)

B (

a.u.

)LFS

HFS

τmid (peak)=25µsperp at LFS midplane

0 5 10 15

(µµ µµs

)ττ ττ ⊥

⊥

⊥

⊥

(pea

k)m

id

V⊥⊥⊥⊥ =3.0km/smid

V⊥⊥⊥⊥ =0.4km/smid

0

20

40

60

80

100

0

1

2

3

V⊥⊥ ⊥⊥m

id (

km/s

)

0 5 10 15

∆∆∆∆rmid (cm) field lines to LFS first wall

LFS

~LCHFS/Cs

~convection time scale

ELM crash

6. Summary

The installation of FSTs enables to access new regimes.

• High ββββN exceeding no wall ideal limitββββN~4.2 (=ideal wall limit)Small critical rotation of V C/VA=0.3% and no increase of critical rotation velocity in high C ββββ regime for suppressing RWM���� High ββββN in ITER and DEMO

• Long sustainment of integrated performanceββββNHH98(y,2)=2.2 for 23.1 s (~12 ττττR) with f BS=36-45%���� ITER hybrid scenario

� Development of real time control methods for pressure profile control and current profile control.

���� intelligent control for the high f BS plasmas in DEMO

• Progress in physics studies implicated for ITER.NTM suppression, Energetic ions with AEs and ELM.

• JT-60SA (super advanced) design is optimized to supp ort and supplement ITER toward DEMO. (M. Kikuchi, FT2-5, Fri.)

JT-60U

Presentations from JT-60U

Mon. Long high ββββN dischargesBootstrap sustained discharges

Tue. ITB study in high ββββp mode plasmasHigh bootstrap discharges

Wed. FSTs effects on rotation & momentum transport

Thu. NTM suppression by ECCDFSTs effects on pedestal and confinementEnergetic ions with AEsCurrent profile control & off-axis current driveParticle control under wall saturationHydrogen retention and carbon depositionRadiation processes of impurities and hydrogenITB study in RS plasmasInstallation of FSTs

Fri. High ββββN and RWM studyELM propagation and fluctuation in SOLSpontaneously excited waves near ICRF

Sat. High density limit with high liNTM suppression by ECCDHigh ββββN and RWM study

JT-60U

N. Oyama (EX/1-3)Y. Takase (EX/1-4)

S. Ide (EX/P1-5)Y. Sakamoto (EX/P1-10)

M. Yoshida (EX/P3-22)

A. Isayama (EX/4-1Ra)H. Urano (EX/5-1)M. Ishikawa (EX/6-2)T. Suzuki (EX/6-4)H. Kubo (EX/P4-11)K. Masaki (EX/P4-14)T. Nakano (EX/P4-19)K. Ida (EX/P4-39)K. Shinohara (FT/P5-32)

M. Takechi (EX/7-1Rb)N. Asakura (EX/9-2)M. Ichimura (EX/P6-7)

H. Yamada (EX/P8-8)A. Isayama (EX/4-1Ra, P)M. Takechi (EX/7-1Rb, P)