Laser Fusion Experimental Reactor LIFT

Based on Fast Ignition and the Issue

T. Norimatsu

Presented at

IAEA-TM on Physics and technologies of IFE target and chambers

March 18, 2015

ILE, Osaka

Outline

• Introduction

– Laser Fusion Experimental Reactor, LIFT

• Critical issue in Phase I

– Heating efficiency

– Radiation safety

– Target stability

– Beam steering

ILE, Osaka

Fast ignition has potential to

achieve ignition and burn with

smaller laser energy

• Since fast ignition needs no hot central core, high gain can be achieved with smaller laser energy than that for central ignition.

• FI is robust to RT instabilities

Key point is the heating efficiency.

ILE, Osaka

Conceptual design committee for

experimental reactor was organized on

Feb. 2012 with support of IFE Forum.

• Chair Y. Kozaki, Co-chair T. Norimatsu, S. Fujioka

Advisory group

K. Ueda, A. Endo, Y. Ogawa, Y. Kato, H. Kan, M. Kikuchi, H. Tanigawa, K. Tobita, M.

Nishikawa and K. Tomabechi

Core plasma group

H. Shiraga

Y. Arikawa

T. Ozaki

H. Sakagami

K. Shigemori

T. Jhozaki

A. Sunahara

T. Taguchi

M. Nakai

H. Nagatomo

H. Nishimura

S. Fujioka

M. Murakami

Fueling group

T. Norimatsu

A. Iwamoto

T. Endo

N. Sato

R. Tsuji

H. Yoshida

Laser group

H. Fujita

T. Kawashima

R. Yasuhara

T. Yanagitani

Plant system group

K. Okano

Y. Ueda

R. Kasada

Y. Kajimura

Y. Kitagawa

T. Goto

M. Kondo

K. Tomabechi

T. Hayashi

T. Fukada

S. Fujioka

T. Norimatsu

The goal of this committee is to

clarify scenario, specification and

issue of experimental reactor.

Name, contributions from MCF

ILE, Osaka

Milestone of experimental reactor

Phase １ Phase ２ Phase ３

Purpose Repeated fusion burns

Physics

Send electric power to net

< 8MW

Tritium breeding

Material test

Operation mode 100 shots 1 week 0.5 year

Fusion yield 16MJ for phys. 40MJ for

technol.

40MJ 40MJ

Electric power No cooling system ～10MWe 40MWe

Gain 100 100 100

Laser energy 650kJComp. 500＋Heating 150,

2 omega, 30ps

650kJComp. 500＋Heating 150,

2 omega, 30ps

650kJComp. 500＋Heating 150,

2 omega, 30ps

Chamber type Solid wall, SUS316No W armor

1st, Solid wall, Ferrite Liquid wall

Blanketト No blanket

Average temperature

increase by 200 oC

①Solid breeder, water

cooling

①LiPb self cooling

Chamber radius 3.5m 3.5m 1.5m

The laser system will be commonly used for all phases.

ILE, Osaka

LD pumped, cooled Yb:YAG ceramic

laser will be used in all phases

Implosion laser Heating laser

Energy (kJ) 600kJ 200kJ

Pulse width TBD 30ps, 1ps rise time

Repetition rate 4Hz 4Hz

Wave length 3ω 2ω

Focusing spot size TBD 66 µm

Energy of fundamental wave 860kJ 500kJ

Number of 32kJ module 28 16

The conversion efficiency for electricity to laser is estimated to be 12%

including the energy for cooling.

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Layout of LIFT

Laser bay Switch yard

PhaseⅠTarget

factory and

TRSUtility area

PhaseⅡ

Power

genera

torWater tank for

neutron shield

PhaseⅢ

Main amp

for heating

laser

Main amp

for compression

laser

PhaseⅢchamber

PhaseⅡchamber

Phase Ⅲ heat exchanger Phase Ⅱ heat exchangerCondenser

Generator

Phase Ⅰchamber

Laser support area

Spatial filter

Pulse compressor

管理研究棟

Water tank for neutron shield

E-field rotator

Adjuster of OPL

Beam switch

box Target factory

and tritium recovery

system

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Radiation control for Phase III

Laser

Anti vibration

pads

Flexible joint

Emergency

valve

Neutron filter

2nd vacuum window

1st vacuum window

Steering mirror

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Neutron and tritium barriers for

beam line

Laser

ロボットアーム

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Outline

• Introduction

– Laser Fusion Experimental Reactor, LIFT

• Critical issue in Phase I

– Heating efficiency

– Radiation safety

– Target stability

– Beam steering

ILE, Osaka

Experimental reactor

Commercial reactor

Point design of LIFT target

Requirements for 50MJ output

Core density ⟩ [g/cm3]

Core areal density ⟩ R [g/cm2]

Burn fraction BT

Fusion output Ef [MJ]

+=

2

5.1,1min

7

R

R

RBT

ρρ

ρ

+×==

24

2

5

5.1,1min

7

)(11013.14[MJ]

5

R

R

REB

m

ME DTT

p

FF

ρρρ

ρ

50MJ

50MJ fusion output,

ρ ρR R MF BT

200g/cm3 1.90g/cm2 93um 0.71mg 0.21

300g/cm3 2.35g/cm2 77um 0.60mg 0.25

400g/cm3 2.75g/cm2 68um 0.53mg 0.28

30MJ fusion output,

ρ ρR R MF BT

200g/cm3 1.65g/cm2 83um 0.47mg 0.19

300g/cm3 2.04g/cm2 68um 0.40mg 0.23

400g/cm3 2.38g/cm2 60um 0.35mg 0.25

50MJ

30MJ30MJ

40MJ40MJ

R: 40 μm

Requirement for ρR (2.3 g/cc) will be realized with 390 kJ laser.

Deposition range dependence on heating laser condition

2/12

m

219 m06.1W/cm102.1[MeV]

×=

µ

λµlaserig

h

IT

[MeV]6.0][g/cm2hRTf=ℜ

fR: range reduction/lengthening factor

� depends on stopping power model.

� Hot electron temperature (Wilks’s model)

� Deposition range

1019

1020

1021

1022

1

10

100

Th

ot [

Me

V]

IL [W/cm

2]

1ω

2ω

3ω

0.1

1

10

R [

g/cm

2]

To keep the deposition range < 1.2g/cm2,

IL [W/cm2] < 5x1019 (1ω),

2x1020 (2ω),

4x1020 (3ω)

The heating lase must be 2ω.

ρ[g/cc] Eheating[kJ] Heating time[ps] Spot size[µm] Intensity[W/cm2] Eheating laser[kJ](coupling eff.)

200 39 30 30 0.46×1020 195 (0.2) / 390 (0.1)

300 18 21 20 0.69×1020 90 (0.2) / 180 (0.1)

400 11 17 15 0.90×1020 55 (0.2) / 110 (0.1)

500 7 14 12 1.10×1020 35 (0.2) / 70 (0.1)

For 300g/cm3 core, required laser intensity (under the optimal condition & laser spot = beam spot) is

IL = 3.5x1020W/cm2 (ηL->core=20%) ~ 6.9x1020W/cm2 (ηL->core=10%).

Summary for heating laser

300 g/cm3 core design

wavelength iglaser = 0.53 m (2 )

Energy Eiglaser ~ 200 kJ

Intensity Iiglaser ~ 2x1020 W/cm2

Spot riglaser ~ 33 m

Duration iglaser ~ 30 ps

Coupling eff. ηiglaser = 20%

Electron T Th ~ 2 MeV

Radius of heat ing rb = 33 µm

Beam guide is important

Energy of heating laser can be reduced with higher ρ.

ρ [g/cm3] Eiglaser [kJ] Iig

laser[W/cm2] iglaser[ps]

300 161 2.24x1020 21

400 125 2.15x1020 17

500 114 2.38x1020 14

Heating process

Experimental check

required

→To be improved

In FIREX-1

Model for heating process

Physical process consists of 3 major elements

Energy of heating laser to that of hot electrons

Fraction of hot electrons that reach the core

Energy deposition efficiency

ILE, Osaka

To improve the coupling efficiency, we

successfully reduced the temperature of

electron beam.2013

before

cool REB

TREB1 = 1 MeV (4%)

TREB2 = 3 MeV (7%)

TREB3 = 15 MeV (89%)

TREB1 = 1.7 MeV (52%)

TREB2 = 10 MeV (48%)

2014

after

cool REB

1

Peak/Foot

＞1011

ILE, Osaka

Self-generated B-field

Magnetic field generated by fast electrons

( ) ( )ff jjBt

B rr

×∇+×∇+

×∇×−∇=

∂∂

ηηµη

0

Extended &

Tapered cone tip

Pointed tip Cone

Gradient of conductivity reflects

electrons and generates magnetic field.

ILE, Osaka

z [∝m]

0 50 100

r[µ

m]

r[µ

m]

050

050

r[µ

m]

050

100

z [∝m]

0 50

B

nf

energy

dep. 0 1 2 30

5

10

η fe->

core

[%

]External B

z [kT]

DLC Tongari Au flat top

x 2.6 (Self B)

x 3.4 (External B)

x 8.6

Self-generated BSelf-generated

+External B(1 kT)Coupling efficiency of

electrons to core

We can expect increase of heating

efficiency by 10 times with a

magnetic field.

ILE, Osaka

Compression

(9 of 12)

Inner High-Z coatingDLC cone

TONGARI-tip

External magnetic coil

B-generation

(3 of 12)

Laser-driven capacitor

Heating

(4 of 4)

*S. Fujioka et al., EPS-ICPP (2012).

Target design to improve the

coupling efficiency

e-

e-Ion+

Ion+

Fundamental equations of radiation hydrodynamics

for laser plasma simulation with magnetic field transport

( ) rLeieee SSQTP ++−∇⋅⋅∇−⋅∇−= κu

dt

dρ

ε

• mass equation• momentum equation

• ion energy equation• electron energy

• radiation transportThermal conductivity tensor

{ } { }

⋅×∇×∇−××∇=

∂∂

hBhBVB

)(4

0

ee

e

ne

cm

e

c

t τα

π

• magnetic field transport

eiceτωββαα ′′′′′′ ,,, : thermal transport coefficient*, which depend on Hall parameter

h : unit vector of magnetic field direction

*S. I. Braginskii, Reviews of Plasma Physics 1, 1965

BBBu

)(4

1)

8P(

dt

dρ

2

th ∇⋅++−∇=ππ

Lorentz force term

Cone-guided implosion (“Rad-Hydro”+”B-field”)

(2D ALE-CIP Radiation-Hydro code)

Implosion Laser condition

Gaussian pulse shaping (FWHM 1.2 ns)

Wavelength ：0.53µm

Energy (on target) ： 2.5 kJ

Magnetic field : 300 T (3 MG)

computational grids：300（i- dir.)ｘ300（j – dir.）

Shell Target：CD 8µm

axial symmetry

250µm

i

jGold cone

30°(Full angle)

PINOCO� 2 temperature plasma

� Hydro ALE-CIP method

� Thermal transport� flux limited type Spitzer-Harm

� Implicit (9 point-ILUBCG)

� Radiation transport� multi-group diffusion

approximation

� Implicit (9 point-ILUBCG)

� Opacity, Emissivity (LTE, CRE)

� Magnetic field

� Laser energy� 1-D ray-trace

� EOS� QEOS (Tomas-Fermi+Cowan)

B

The magnetic field is compressed. However, the hydrodynamic instability is seeded at early phase of the implosion by the anisotropic of thermal conductivity.

t=1.34 ns

w/o magnetic field consideration

with magnetic field effect

middle; mass density lower: density

ILE, OsakaPhoto of capacitor-coil target

H. Daido et al., PRL (1995), C. Courtois et al., JAP (2005).

1mm

B

Current ~ several MA

kJ-ns laser beams

2n

dd

isk

w/h

ole

1s

td

isk

One-turn coil

1T B field was generated with

laser-driven capacitor and coil

ILE, Osaka

S. Fujioka et al., Sci. Rep. (2013).

λL = 1.053 µm

Faraday rotation

measurement

Pick-up probe

measurement

λL = 0.53 µm

1 T B field was obtained.

ILE, Osaka

Fire ring target would be the

solution for the coupling efficiency.

Current

B

Laser

Timing of B field and τB

are the key of success.

Fin to generate ring current

ILE, Osaka

Control of fast electrons by magnetic

field seems the key point to improve

the heating efficiency.

• Numerical simulation indicated that the heating efficiency can be increased with the external B by a factor of 8 and with self-generated B by a factor of 2.6.

• Next issue; How to create the external B field?

Fire ring target would be the solution.

ILE, Osaka

Outline

• Introduction

– Laser Fusion Experimental Reactor, LIFT

• Critical issue in Phase I

– Heating efficiency

– Radiation safety

– Target stability

– Beam steering

ILE, Osaka

Operation scenario of Phase I

• Physical experiments 16MJ x 1Hz X100s

• Reactor technology exp. 40MJ X 1Hz X 1s

• Chamber material SUS316, No blanket,

No W armor

• 1 campaign /month, X 3 years.

• Conventional transmitting optics can be

used.

• Tritium in vacuum line will be recovered

and reused in the next campaign after

isotope separation

• 1/3 of tritium will be remained in the

chamber surface.約40m

ILE, Osaka

Thermal load by a particles on the 1st

wall 4J/cm2. We accept melting of the

surface because of limited use.

Thermal load by x-ray (left) and particle (right).

Fusion yield 200MJ, R=3m

Temperature at inner surface during 100 shots

Temporal temperature change at the last shot

Melting 5µｓ

At surface

At 5µｍ

Evaporation speed is 1.8✕10-10cm, which shows no

influence on the chamber safety

Temperature along the cross section of wall at the

last shot

ILE, Osaka

Radiations in Phase I

• E x B acceleration of electrons by heating laser 1

～ 40 MeV, at 10ns after laser shot

– Hard x-rays by these electrons cause (g, n)reactions in

chamber wall

• Nuclear reactions at chamber

– (n, 2n), (n, p), (n, np), (n, d), (n, α)….

• Neutron captures ～ 9MeV, 70ns-80ns

• Decay radiations ～ 3MeV, µs ～106 year (93Zr)

ILE, Osaka

Nuclear reactions in SUS316

Neutron captures radiate intense γ-rays

原子番号 49Cr 生成確率 崩壊形式 半減期反応プロセス(親元素存在率、14MeV中性子衝突断面積（ｇは

対熱中性子）)

(n,g)のγ線エネルギー(keV)

中性子捕捉によるγ線エネ

ルギー（J)

2H 8.55E-04 安定

52Cr(n,d)51V(84%3.8mb),53Cr(n,d)52V(10%2.9mb)58Ni(n,d)57Co(58%8.1mb)61Ni(n,d)60Co(1.1%2.9mb)62Ni(n, d)61Co(3.6%0.9mb)92Mo(n,d)91Nb(15%2.3mb)94(n,d)93Nb(9.3%1.0mb)

95Mo(n,d)94Nb(15%1.4mb)

3H 1.00E-06 β- 12.3y52Cr(n,t)50V(84%4e-15b)61Ni(n,t)59Co(1.1%0.1mb)

94Mo(n,t)92Nb(9.3%0.015mb)

Z=2 4He 1.48E-02 安定

56Fe(n,a)53Cr(92%41mb),54Fe(n,a)51Mn(5%,83mb),52Cr(n,a)49Ti(84%35mb),50Cr(n,a)47Ti(4%73mb),53Cr(n.a)50Ti(10%48mb),

54Cr(n,na)51Ti(2.4%0.83mb),54Cr(n,a)51Ti(2.4%,12mb),57Fe(n,a)54Cr(2.1%11mb),58Ni(n,a)54Fe(58%3.5mb),58Ni(n,a)55Fe(58%105mb)60Ni(n,na)57Fe(26%10mb)60Ni(n,a)57Fe(26%68mb)

61Ni(n,na)58Fe(1.1%3.5mb)61Ni(n,a)58Fe(1.1%46mb)62Ni(n,na)58Fe(3.6%0.5mb)64Ni(n,a)61Fe(0.9%5.6mb)92Mo(n,a)89Zr(14.8%21mb)94Mo(n,na)90Zr(9.3%5.9mb)94Mo(n,a)91Zr(9.3%17.5mb)95Mo(n,a)92Zr(16%13mb)

96Mo(n,na)93Zr(17%0.99mb)97Mo(n,na)93Zr(9.5%0.56mb)97Mo(n,a)94Zr(9.5%6.8mb)

98Mo(n,na)94Zr(24%0.29mb)98Mo(n,a)95Zr(24%5.1mb)

47Ti 1.37E-04 安定 50Cr(n,a)47Ti(4%73mb)49Ti 1.46E-03 安定 52Cr(n,a)49Ti(84%35mb)

50Ti 1.89E-04 安定53Cr(n.a)50Ti(10%48mb)54Cr(n,a)51Ti(2.4%,12mb)

51Ti 2.50E-05 β- 5.76m 54Cr(n,na)51Ti(2.4%0.83mb)

49V 8.79E-04 ε 330d50Cr(n,np)49V(4%223mb),

50cr(n.d)49V(4%15mb)50V 2.48E-03 安定 50Cr(n,p)50V(4%284mb)

51V 1.30E-03 安定52Cr(n,np)51V(84%30mb),52Cr(n,d)51V(84%3.8mb)

52V 1.01E-02 β－ 3.743m52Cr(n,p)52V(84%88mb),

53Cr(n,np)52V(10%2.1mb),53Cr(n,d)52V(10%2.9mb)

53V 2.98E-04 β－ 1.543m 53Cr(np)53V(10%44mb)54V 4.10E-05 β－ 49.8s 54Cr(n,p)54V(22.4%12mb)

Z=1

Z=22

Z=23

49Cr 2.50E-05 β＋ 42.3m 50Cr(n,2n)49C5(4%8.2mb)50Cr 7.66E-02 安定

51Cr 2.81E-02 ε 27.7d50Cr(n,g)51Cr

54Fe(n,a)51Mn(5%,83mb),52Cr(n,2n)51Cr(84%258nb)

749 6.04E+04

52Cr 8.68E-01 安定53Cr(n,2n)52Cr(10%698mb),53Cr(n,2n)52Cr(10%698mb)

53Cr 2.07E-01 安定56Fe(n,a)53Cr(92%41mb),52Cr(n,g)53Cr(84%775mb),

54Cr(n,2n)53Cr(2.4%676mb)7938 4.71E+06

54Cr 3.59E-02 安定53Cr(ng)54Cr(10%18b),

57Fe(n,a)54Cr(2.1%11mb)834 8.58E+04

55Cr 7.40E-05 β－ 3.497m 54Cr(n,g)55Cr(2.4%0.34mb) 6246 1.32E+03

Z=24

57Ni 1.28E-03 ε 35.6h 58Ni(n,2n)57Ni(58%31mb)58Ni 9.62E-01 安定

59Ni 2.40E-02 ε 7.6e4y58Ni(n,g)59Ni(58%4.6b)

60Ni(n,2n)59Ni(26%388mb)8998 6.17E+05

60Ni 2.37E-01 安定 61Ni(n,2n)20Ni(1.1%929mb)

61Ni 2.00E-02 安定60Ni(n,g)61Ni(26%2.9b)

62Ni(n,2n)60Ni(3.6%808mb)7819 4.49E+05

62Ni 6.87E-02 安定 61Ni(n,g)62Ni(1.1%2.5b) 1172 2.31E+05

63Ni 3.06E-03 β－ 101.2y62Ni(n,g)63Ni(3.6%14.2b)

64Ni(n,2n)63Ni(0.92%1021mb)6838 6.00E+04

64Ni 8.42E-03 安定65Ni 4.70E-05 β－ 2.517h 64Ni(n,g)65Ni(0.92%1.48b) 6034 8.12E+02

ε ４．161mIT 4.161m

90Zr 0.00E+00 安定 94Mo(n,na)90Zr(9.3%5.9mb)91Zr 1.40E-05 安定 94Mo(n,a)91Zr(9.3%17.5mb)

92Zr 6.10E-05 安定95Mo(n,a)92Zr(16%13mb)

96Mo(n,na)92Zr(17%0.99mb)

93Zr 3.10E-05 β－ 1.61e6y96Mo(n,a)93Zr(17%9.7mb)

97Mo(n,na)93Zr(9.5%0.56mb)

94Zr 1.20E-05 安定97Mo(n,a)94Zr(9.5%6.8mb)

98Mo(n,na)94Zr(24%0.29mb)95Zr 5.00E-06 β－ 64.0d 98Mo(n,a)95Zr(24%5.1mb)96Zr 0.00E+00 安定97Zr 5.00E-06 β－ 16.79h

92Mo(n,a)89Zr(14.8%21mb)Z=40

89Zr 9.00E-06

Z=28

Total Gamma ray energy due to

neutron capture is estimated to

be 65kJ/m2 in 10ns～0.1µｓ

53Mn 6.84E-03 ε 3.7e6ｙ 54Fe(n,np)53Mn(5.8%490mb)54Mn 9.68E-03 ε 312d 54Fe(n,p)54Mn(5%.367mb)55Mn 1.24E-02 安定 56Fe(n,np)55Mn(92%, 71mb),

56Mn 3.98E-02 β－ 2.5789h56Fe(n,p)56Mn(92%, 114mb).57Fe(n,np)56Mn(2.1%1.8mb)

57Mn 1.97E-04 β－ 85.4s 57Fe(n,p)57Mn(2.1%30mb)β－ 3sβ－ 65.4sIT 2.54mε 8.5m

54Fe 2.88E-01 安定 58Ni(n,a)54Fe(58%3.5mb)

55Fe 1.23E-01 ε 2.744y54Fe(n,g)55Fe(5.8%2.25b)

56Fe(n, 2n)55Fe(92%, 389mb),58Ni(n,a)55Fe(58%105mb)

9297 7.79E+05

56Fe 4.11E+00 安定57Fe(n,2n)56Fe(2.1%943mb)60Ni(n,na)56Fe(26%10mb)

57Fe 1.77E-01 安定

56Fe(n,g)57Fe(92%2.59b)58Ni(n,2p)57Fe(58%12mb)61Ni(n,na)57Fe(1.1%3.5mb)60Ni(n,a)57Fe(26%68mb)

7631 3.87E+06

58Fe 1.62E-02 安定57Fe(n,g)58Fe(2.1%2.5b)61Ni(n,a)58Fe(1.1%46mb)

62Ni(n,na)58Fe(3.6%0.5mb)810 3.76E+04

59Fe 1.53E-04 β－ 44.495d 58Fe(n,g)59Fe(0.3%2.3b) 287 1.26E+0261Fe 2.00E-06 β－ 5.98m 64Ni(n,a)61Fe(0.9%5.6mb)56Co 1.00E-06 ε 77.2d 58Ni(n,p)58Co(58%330mb)

57Co 2.30E-02 ε 271d58Ni(n,np)57Co(58%635mb),58Ni(n,d)57Co(58%8.1mb)

58Co 2.03E-02 IT 9.10h

59Co 1.61E-03 安定60Ni(n,np)59Co(26%134mb)60Ni(n,d)59Co(26%3.9mb)61Ni(n,t)59Co(1.1%0.1mb)

IT 10.467mβ－ 10.467mβ－ 1925d

61Co 7.80E-05 β－ 1.65h61Ni(n,p)61Co(1.1%61mb)

62Ni(n,np)61Co(3.6%0.7mb)62Ni(n, d)61Co(3.6%0.9mb)

β－ 1.54mβ－ 13.86m

64Co 1.00E-06 β－ 0.30s 64Ni(n,p)64Co(0.92%9.1mb)

54Fe(n,2n)53Fe(5%,1.2mb)

60Ni(n,p)60Co(26%157mb)61Ni(n,np)60Co(1.1%15mb)61Ni(n,d)60Co(1.1%2.9mb)

62Ni(n,p)62Co(3.6%24mb)

58Mn 1.20E-05

Z=25

53Fe 2.90E-05Z=26

Z=27

60Co 3.35E-03

62Co 8.00E-05

91Nb 7.39E-04 IT 3.76μs92Mo(n,np)91Nb(15%0.14mb)92Mo(n,d)91Nb(15%2.3mb)

92Nb 2.82E-04 安定92Mo(n,p)92Nb(15%128mb)

94Mo(n,t)92Nb(9.3%0.015mb)

93Nb 1.20E-05 安定92Mo(n,g)93Mo(15%21mb)

94Mo(n,np)93Nb(9.3%16mb)94(n,d)93Nb(9.3%1.0mb)

94Nb 6.60E-05 β－ 6.263m94Mo(n,p)94Nb(9.3%53mb)95Mo(n,np)94Nb(16%8.4mb)95Mo(n,d)94Nb(15%1.4mb)

β－ 3.61dIT 3.61d

β－ 35.0d

96Nb 1.70E-05 β－ 23.4h95Mo(n,g)96Mo(15.9%14b)

96Mo(n,p)96Nb(16.7%21mb)97Mo(n.p)97Nb(9.5%15mb)

IT 58.7sβ－ 72.1mβ－ 2.86sβ－ 51.3mβ－ 15sIT 2.5m

β－ 2.6mβ－ 1.5s

2.99s91Mo 1.79E-04 IT 64.6s 92Mo(n,2n)91Mo(14.8%151mb)92Mo 3.37E-02 安定

IT 6.85h 943 1.02E+02ε 6.85h

94Mo 2.21E-02 安定

95Mo 4.11E-02 安定94Mo(n,g)95Mo(9.3%13mb)95Mo(n,2n)94Mo(16%1.35b)96Mo(n,2n)95Mo(17%455mb)

7165 3.46E+03

96Mo 4.21E-02 安定 97Mo(n,2n)96Mo(9.5%1.4b)

97Mo 2.43E-02 安定96Mo(n.g)97Mo(17%596mb)98Mo(n,2n)97Mo(26%1.33b)

481 7.59E+03

98Mo 5.17E-02 安定 97Mo(n,g)98Mo(9.5%1.0b) 787 1.17E+0599Mo 1.80E-03 β－ 65.976h 98Mo(n,g)99Mo(24%130mb) 97 4.99E+02100Mo 2.08E-02 ２β－ 7.3E18y101Mo 1.86E-04 β－ 14.6m 100Mo(n,g)101Mo(9,6%199mb) 180 9.59E+01

ε 51..5mIT 51.5m

7.65E+00 合計 1.06.E+07

92Mo(n,g)93Mo(14.8%21mb)94Mo(n,2n)93Mo(9.3%1.1b)

95Mo(n.p)95Nb(16%35mb)96Mo(n,np)95Nb(16.7%1.4mb)

96Mo(n,d)95Nb(16.7%

1.10E-05 98Mo(n,np)97Nb(24%0.12mb)

100Nb

97Nb

98Mo(n,p)98Nb(24%4.8mb)

100Mo(n,2n)99Nb(9.6%1.39b)

100Mo(n,p)100Nb(9.6%1.8mb)

93Mo

96Tc 2.00E-06

Z=41

Z=42

Z=43

95Nb 4.90E-05

1.00E-06

1.28E-03

99Nb 0.00E+00

98Nb 1.90E-05

Plasma dyagonostic system must work and keep the data

under <９MeV、６５kJ/m2 γ-rays

ILE, Osaka

Neutrons hit the chamber wall 70 ns after

fusion burn and release γ rays (<9 MeV) in 10ns.

• The intensity of g-rays at the chamber surface is estimated to be 6.5x109 W/cm2

ILE, Osaka

Radiation from the chamber

after 100 shots in Phase I

0.01

0.1

1

10

100

1000

104

10 100 1000 104

105

106

107

108

Gamma ray power generated in SUS316 chamber wall after 16MJ, 100 shots of Phase I

Elapsed time (sec)

6M

1 H

10 H

1 D

10 D

0.0001

0.001

0.01

0.1

1

10

100

1000

10 4

1 10 100 1000 104

105

106

107

Gamma ray power generated in the concrete base of the target chamber after 16MJ x 100 shots

Time (s)

1 hour

30 day

1 day

Energy of main g ray 3MeV

0.4Sv/h at 1 hour after 100 shots

Energy of main g ray 1.3MeV

9Sv/h at 1 hour after shots

10Sv/h

1mSv/h

From SUS 316 chamber From base concrete

ILE, Osaka

Accumulation of long-life-time RIs in

Phase I is acceptable.

原子番号 核種 生成確率 崩壊形式 半減期 半減期(秒）100ショット後

(Bq)主なガンマ線MeV(相対頻度）

線量率MeV/Bq/s

Z=1 3H 1.00E-06 β- 12.3y 3.9.E+08Z=23 49V 8.79E-04 ε 330d 2.9.E+07 1.3.E+10 0.0045(11%) 5.15E-04Z=24 51Cr 2.81E-02 ε 27.7d 2.4.E+06 4.8.E+12 0.32(9.9%) 0.0317Z=25 53Mn 6.84E-03 ε 3.7e6ｙ 1.2.E+14 2.4.E+04 0.005(15%) 7.90E-04Z=25 54Mn 9.68E-03 ε 312d 2.7.E+07 1.5.E+11 0.834(100%) 0.8346Z=26 55Fe 1.23E-01 ε 2.744y 8.6.E+07 5.8.E+11 0.005９（16%) 9.60E-04Z=26 59Fe 1.53E-04 β－ 44.495d 3.8.E+06 1.6.E+10 1.099(57%),　1.291(47%) 0.621，0.558Z=27 57Co 2.30E-02 ε 271d 2.3.E+07 4.0.E+11 0.122(85%) 0.104Z=27 60Co 3.35E-03 β－ 1925d 1.7.E+08 8.2.E+09 1,173(100%),1.332(100%) 1.17，1.33Z=28 59Ni 2.40E-02 ε 7.6e4y 2.4.E+12 4.1.E+06 0.007(20%) 0.00136Z=28 63Ni 3.06E-03 β－ 101.2y 3.2.E+09 3.9.E+08 No dataZ=40 93Zr 3.10E-05 β－ 1.61e6y 5.1.E+13 2.5.E+02 0.016(4.7%) 7.80E-04Z=40 95Zr 5.00E-06 β－ 64.0d 5.5.E+06 3.7.E+08 0.756(54%) 0.4115Z=41 95Nb 4.90E-05 β－ 35.0d 3.0.E+06 6.6.E+09 0.765(99.8%) 0.7643

Long-life -time RIs

BG radiation in Phase I

54Mn (3✕1012Ｂｑ) is the main element.

The dose rate is estimated to be 10mSv/h

Amount of radio active waste after Phase I

Weight(to

n)

Main RI Clearance

level

After 50

years

After 100

years

After 150

years

Chamber 90 60Co 0.1 Bq/g No Disposal Disposal

Concrete

base

(upper 1m)

60 152Eu - 120Bq/g 9.2Bq/g 0.7Bq/g

Concrete of

room wall27000 152Eu - 8.3Bq/g 0.63Bq/g 0.05Bq/g

ILE, Osaka

Outline

• Introduction

– Laser Fusion Experimental Reactor, LIFT

• Critical issue in Phase I

– Heating efficiency

– Radiation safety

– Target stability

– Beam steering

ILE, Osaka

Scenario for fueling

n=20 x 80 (for 13 min at 2 Hz)

12 cm

Air lock

Air lockAir lockCooling zone Freezing zoneLoading zone

Liquid N2

Liquid He

20 K He

100 torr19 K DT

128 torr

19 K DT

128 torr

10 K DT

1 torr

DT

Pump

DT

Pump

2nd Tritium barrier

Vacuum vessel

3 hr

Vacuum

Pump

TRS IS &

Strage

To injector

Laser

I

Phase IPhase II and later

ILE, Osaka

Thermal cavitation technique

enables batch filling

• Fill time by conventional diffusion is >24 h. Resulting large tritium inventory and accumulation of 3He

Low density foam

Fill gap

Liquid DT Vaporization

Fill completed

ILE, Osaka

Loading of FI targets in sabots

Sabot loading section

（Similar system was proposed by E. Koresheva)

Large revolver allows sufficient time to cool

Sabot

Target

Gas reservoir

From DT fill station

Gas

Target

ILE, Osaka

Injection system consists of gas gun

followed by coil gun and tracking section.

仕様Injection velocity 100+/-2 m/s

Rep rate 2 Hz

Pointing +/- 1 mrad

Operation power including freezer

500 kW

投入追尾

Divergence of flight direction and

tumbling of target must be

experimentally checked.

ILE, Osaka

Real size injection system was

constructed at ILE to check the stability of

FI target after sabot release.

42

ILE, Osaka

First campaign revealed

“tumbling” is the issue.

43

V=88 m/s, P=10 Pa

Velocity (m/s) Pointing

(mrad)

Tumbling (deg at

Fire position)

Final goal of

gas gun

90+/-5 +/-1 +/- 2

Result 88+/-3 +/-0.6 5.4+/-6

Piled contours of 10 shots at

1.7m from the muzzle

Estimated angle at muzzle and release pointIn three cases, tumbling at muzzle was larger than observed.

Observed at 1.72m Estimated at muzzle0 -0.2m

-0.15

130312-#6+14 +16 -0.14

130312-#1 E+5.1 +2.8

130312-#2+8.0 +5.3 -1.1

130312-#3-2.9 -4.1

-0.11

130312-#4+9.7 +6.9

-0.19

-1.1

130312-#5+5.6 +3.3

130312-#7 +8.9 +8.9 -0.23

-0.11

130312-#9-2.3 -5.4 -0.14

130313-#1-0.10-2.3 -0.1

130312-#8 +8.9 +6.6

88.2m/s

82.3m/s

87.4m/s

77.0m/s

79.6m/s

79.6m/s

85.2m/s

75.9m/s

70.3m/s

80.1m/s

To check the influence of B-field, plastic targets were injected

Experiment 1：aluminum target→plastic target

Gunn tube Gunn tube

Magnet

Experiment 2：stabilization by spin

Fig.5 Aluminum dummy target Fig.6 Plastic dummy taget

Fig.7 Without B-field Fig.8 With rotating B field

実験結果

0

100

200

300

10m地

点傾

き変

化量

[deg]

Plastic D. T.Al D.T. with

spin

���. �.

���� �

Al Dummy

target (D. T.)

Plastic dummy targets showed better repeatability in tumbling.The absolute tumbling angle should be reduced. (Final goal is +/- 2 degree)

Experimental results

Est

ima

ted

tu

mb

lin

g a

ng

le a

t 1

0m

fro

m

mu

zzle

(d

eg

)

ILE, Osaka

Issue to be checked

• Is deceleration by eddy current unstable for FI target?

•

• In our calculation, 50 µm off-center between target and B

field results in 108 deg tumbling at 10m from the muzzle.

• Next plan

– Q pole layout where Bz=0 at the center

– Helical layout to induce target spin

3.9 mm

15o9 mm11 mm

5.4 mm3 mm4.0mm

Plastic coating

Prabolic mirror

Foam insulator Solid DT+Foam

Mas center Center for deceleration

ILE, Osaka

Summary

• To reduce the gap between single-shot, fusion burn and commercial reactor, Laser fusion experimental reactor LIFT with 3 phases was proposed.– Phase I, repeated fusion burns,( 1Hz 100 shots )

– Phase II, power generation ( < 1 week)

– Phase III long time operation (0.5 year)

• Critical issues in Phase I are the heating efficiency, tumblingof injected target, and dumping of steered mirror.

• Thank you for your attention!

ILE, Osaka

Steering mirror will be driven with an array of PZT-

actuators.

Response was confirmed with a small mudule.

22nd IAEA FEC2008 at Geneva yos081002-49

940g

300mm

Al Mirror

PZT:

PFT-1100

0-150V

0-63µm

He-Ne Laser

Large Sized Steering Mirror

PZT-actuator array

Base

Size : ~1m Mass: ~100 kgMoment: ~10 kgm2

+Vx-Vx

-Vy

+Vy

Compens

ator

HV amp & driver

Control signal

Stroke/Distance Resoluti

on

PhaseⅠ ±5mm／20m 100µｍ

PhaseⅡ ±5mm／20m 100µｍ

PhaseⅢ ±5mm／30m 100µｍ

ILE, Osaka

The rise time met the requirement but

the dumping was far from the goal

Time t [s]

Dri

ve v

olt

ag

e v

[V]

Be

am

po

siti

on

z [

mm

]

at

5 m

fro

m m

irro

r

５ｍ

22nd IAEA FEC2008 at Geneva yos081002-50

• Over-shoot must be reduced to 1/100

• Improve support structure

• Mode analysis

LCOS-SLM by Hamamatsu Pho.

Present status：16mm x 12mm

Demonstration using 100mm x 100mm device

with hgh resolution is necessary.

For a compression beam, 8 x 8 =64

modules are necessary.

Concept of beam steering by control of wave-front

Controller

Incident laser

Reflected laser