電子加速器と新量子放射源
失敗に学ぶ

山嵜 鉄夫

2008年9月3日
夜話 OHO’08 @KEK

山嵜 鉄夫履歴書
学歴
1971年

京都大学大学院工学専攻科原子核工学専攻博士課程修了

職歴
1971年

電子技術総合研究所入所
26年 6ヶ月

1998年

京都大学エネルギー理工学研究所に異動
9年 3ヶ月
単身赴任を楽しむ！！

年
2007年

京都大学退職京都大学原子核工学教室
コッククロフト型加速器
ヴァンデグラーフ型イオン加速器

イオンビームの多重散乱

電子技術総合研究所田無分室
40-MeV電子リニアック

加速器の性能向上
高エネルギー放射線標準
放射線遮蔽
新電子 速器施設 設計
新電子加速器施設の設計

電子技術総合研究所（つくば）600-MeV電子リニアック
600
M V電子リニア ク
800-MeV電子蓄積リング
電子蓄積リングNIJI I – IV
小型蓄積リングNIJIシリーズ

電子加速器施設の建設
加速器の性能向上
レーザー・コンプトン散乱
自由電子レーザー・・・・・・・・・・

京都大学エネルギ 理工学研究所
京都大学エネルギー理工学研究所
40-MeV電子リニアック

新量子放射エネルギー

AIST ELECTRON ACCELERATOR FACILITY

STORAGE RING TERASFar UVVUV Detector
Detector
Calibration
Calibration BL3-2
BL3-1
BL3-3

ULSI Lithography

Monochromators
BL2A
2 - 8 nmPolaraizedUR

2920

LANDAUCAVITY

RFCAVITY
11.
7KICKERMAGNET
B445

B7

BL2C
110 - 300 nm

B5B6

BL2B
10 - 60 nm

R=2000e-

POLARIZINGUNDULATOR

QF

BL1B

QD

50 - 300 nm

QF
BL1A
B8
SEEPTUM
MAGNET
B100
18

DCCT

WIGGLER
B2LCS
Laser

B3

Backscattered
Photons

FEL

1 - 25 nm

STORAGE RING TERASLCSFELLaser Induced Compton Backscattering

AIST LCS FACILITY

by H. Ohgaki

example of LCS spectrum

CONCEPTUAL SCHEME OF FELLASERLORENTZ FORCE

Magneticfield

Electron bunch

MIRROR

Force
Electriccurrent

ACCELERATOR
Bending magnet
Electron bunch

LASER
MIRROR

Bending magnet
Bunching

3 major elementsof FEL
FEL device
Optical cavity
Electron beam

FEL EVOLUTION
10τ=0τ = 1/3
τ = 2/3
τ=1864ν

20-2-44a0 = 5j = 10
ν0 = 2.6-6-8-1010-20246ζ81012

Wavelengthg Tunability
y of FEL

λ=λ02(1+K/ 2)
22γ 0
K = 93.4 B0 [T ]λ0 [m]FEL PRJECTS IN THE WORLDFEL PRJECTS IN JAPANOPTICAL KLYSTRONETLOK IETLOK−ICAVITY--LOSS MEASUREMENTCAVITY
Deca Time Method
Decay-Time

Measured Waveform

PM 1PM 2τ

with averagingg g

CAVITY--LOSS MEASUREMENTCAVITY
Decay-Time Method

Purging tube
N2

ROUND-TRIP CAVITY-LOSS

Mechanism of Mirror Degradation

surface degradation

volume degradationOXYGEN
PLASMA
TREATMENT6

HfO2 / SiO2
annealed at 230 °C for 10 hours.

5

MIRROR LOSS (XX10 -3 )RESTORATIONOFMIRROR
DEGRADATION

annealed at 230 °C for 4 hours.

432

1
initial loss

00204060

TIME (min)80100120

X-RAY PHOTOELECTRON
SPECTRAFROM MIRROR SURFACEHfO2/SiO2010

Ei=1 keVinitialdegradedtreated with plasma
and annealing

Normalizzed Countts

Positron lifetime
spectrat off
a dielectric
multilayer cavity
mirror for FEL-110-210-31002

4Time (ns)6

FEL GAIN MEASUREMENTe-45

e-45

BM

OPTICAL KLYSTRONBMAPERTURE

M
F-2VAC.
RFLCCAVITYFILTER

F-1VAC.
MONOCHRO
MONOCHROMATORHM

RFSOURCEλ/2 PLATE

M
DYE
LASER
FUNCTION
GENERATORND FILTER
DETECTORMONOCHROMATOR
E/O
MODULATORFREQ.
DIVIDER
SIG.
HF
LIA
REF.

Ar+LASER

SIG.
REF.

LF
LIA

GAIN OF TERAS FEL

1 64 mA /bunch
1.64

GAIN ( x 10-5 )G

100.85 mA / bunch

0-10240
ELECTRON ENERGY (MeV)245

STORAGE RING TERASFar UVVUV Detector
Detector
Calibration
Calibration BL3-2
BL3-1
BL3-3

ULSI Lithography

Monochromators
BL2A
2 - 8 nmPolaraizedUR

2920

LANDAUCAVITYRFCAVITY
11.
7

KICKERMAGNET
B445

B7

BL2C
110 - 300 nm

B5B6

BL2B
10 - 60 nm

R=2000e-POLARIZINGUNDULATORQF

BL1BQD50 - 300 nm

QF
BL1A
B8SEEPTUMMAGNET
B100
18

DCCT

WIGGLER
B2LCS
Laser

B3

Backscattered
Photons

FEL

1 - 25 nm

main RF cavity
y and Landau cavityyPLC= 0.53
0 53 kWSUPPRESSION OF
COHERENT SYNCROTRON OSCILLATION

sidebandsLasing
gp
pattern of FEL on storage
g ringg TERAS
spatial coherenceNIJI-NIJI-IV
NIJI-IV FELSYSTEMNIJI
IV FELSYSTEM

STORAGE RING NIJINIJI-IVOPTICAL KLYSTRONETLOK−IIGAIN OF NORMAL UNDULATOR & OK
3.0: gd = 56 mm: gd = 38 mm

32.54

GOK / G2N

52.061.57.5
Optimal curve
σγ/γ= 10x10-44101.04050

607080

Nd90100110

GOK= G2N[(N+Nd)/N]ff = exp[-8π (N+Nd) (σγ/γ) ]222

NIJI-NIJI-IV
NIJI-IV FELSYSTEMNIJI
IV FELSYSTEM

SQS SYSTEMS SOF
O NIJI-IVJ

Quadrupole

6-pole6-poleB diBendingBending45
28.5 50

651409096550 28.5

SD: 5.176 A

(a)

2.015
1.5

Horizontal
Vertical
Vi lChromaaticity

1.0
0.5
0.0
-0.5
-1.0

CHROMATICITY CORRECTION
WITH
6-POLE MAGNETS

-1.5
5.0

5.5

6.0

SF Current [A]SF: 5.287A

2.5(b)

2.0
1.5

Horizontal
Vertical

Chromaticitty

1.0
0.5
0.0
-0.5
-1 0
-1.0
-1.5
-2.0
4.5

5.0

5.5

SD Current [A]SF = 5.09 A, SD = 4.99 A, for x = 0
SF = 5.29 A, SD = 5.18 A, for ξx = 0.15, ξy = 0.08

EFFECT OF CHROMATICITY CORRECTION
Open: before the improvement Solid: after the improvement

167x1016Peak-Electronn Densityy

6x10165x10164x10

163x10162x10Single-bunch Operation
E = 309 [[MeV]]
161x10005101520

Beam Current [mA]

2530

45
4.5
4.0CA
AVITY LOSS (%)

3.5

Al2O3 MIRRORS

3.0
2.5
2.0
1.5
10
1.0
0.5
0.0
210

215

220

225

WAVELENGTH (nm)

230

5UV

VUV

4Gain
n [%]

Inntensityy [ a.u. ]single path gain at 22 mA
single-path

32212 nm
1 196 nm

0150

200

250300350400

450

Wavelength [nm]

500

550

600650MAIN FEATURES OF FEL
Wavelength Tunability

Can we use FELs ?

Polarization Tunabilityy
High Efficiency

PRESENT STATUS OF FELHigh Power
Large Scalewith suchexcellentll t features
f t

Expensive
Low Efficiency of Accelerator
Unexplored Wavelength Region

研究予算のスケーリング
大学

旧国立

旧国立直轄研究所

研究所

研究所

特殊法人研究所

小売商店

スーパーデパート

マ ケット
マーケット
国立大学法人

旧電総研

私立大学

産総研

ＫＥＫ
原研
理研

予算

予算

予算

極小

中規模

極大

CO2

CO

Nd:YA
AG
I+Ar
Ne:HeeRuby

KrF
XeCl

Ar2
F2ArF

ABSORPTION CEFFICIENTS

7106AB
BSORPTIO
ON COFFICCIENT-1(cmm )10H2O
GaAsSi

510410310210110010-110-2210ETL-310KU-FEL-4410-110010

WAVELENGTH (μm)

110iFEL (Osaka Univ.)(former FELI)
ree-Electron
f F
Laser
a University

User Lab.

Control room

Lab.1
L b 2
Lab.2

Beam sharing
systemLab.3

un H VLaser
Lr monitor
it rroom

Lab 4Lab.4
Injector
AT130MeV

FIR120-60
2060 m m

AT2

Optical pipes

AT375MeV

MIR
5-22m mKU FELKU-FELAT5AT6NIR
1-6m
16m m

Accelerator room8m

AT45m

AT7165MeV

UVV
0.23-1.2m m

FIR250-100 m m

KUFEL((includingg RF sourceand drive laser)

UJI CAMPUS
KYOTO UNIVERSITY

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Lab. for Photon andCharged Particle Research

北4号棟
北3号棟

Keihan Obaku St.

北1号棟
Main Bldg.

Advanced Research Center
for Beam Science

総合研究実験棟
南2号棟
南3号棟
南1号棟

Wood Composite HallJR Obaku St.
Gate

Laboratory for Photon andCharged Particle Research
量子光・加速粒子
総合工学研究棟

PRESENT KUKU-FEL
RF GUN

量子光・加速粒子
総合工学研究棟

dog-legLaboratory for Photon andCharged Particle Research

LERATIN
NG
ACCEL
TUBE
TUNDU
ULATOR

8 MeV

30 MeV

180 arcPRESENT KUKU-FELACCEELERATINNG
TUBE
T180 arc

8 MeV

dog-leg
RF GUNUN
NDULATOOR

30 MeVKU--FEL RESEARCH SUBJECTS
KU
4.5-cavity Themionic RF Gun
Compact RF Modulators
Backbombardment Problem
quantitative measurement
application of dipole magnetic field
modulation of RF waveform
Ti d t
Triode-type
RF gunEmittance Measurement
tomographyg p y method
Simulation of Electron-Beam TransportPhotocathode RF Gun
simulation study
experiments, to be started
Simulation of FEL Process
start-to-end simulation
Design of undulators
planar,lcircular,
il staggeredtd array, SC
Energy Recovery Scheme
radiation shielding
simulation,

Problem in thermionic RF gun (1) ~ back bombardment ~cathodeRF window

laser window

vacuum pump

1 dimensional model
CathodeheaterQb(x,τ)BackBkstreaming
electrosQh
thermioniccathodex

Problem in thermionic RF gun (1) ~ back bombardment ~Back-streaming electrons hit the cathode.
C th d temperature
Cathodettiincreases.
y on cathode surface
Current density
increases.
Time evolution of electron beam andinput/reflected RF power

thermioniccathodeBeam loading increases and thenresonantt ffrequency off cavity
it changes.
hBeam current becomes unstable.
Maximum pulse duration is limited
to at most several μ sec.

10

reducing the effectof backbombardment
by adjusting the RF waveform
experimental

Pow
wer [MW]86
Modulated RF

4

Flat RF20

Adjustment ofthe RF waveform
0246Time [μsec]

8109.0100
Flat RF

8.5

Modulated RFEneergy [MeVV]

Currrent [mAA]

80
6040200246Time [μsec]
beam waveform

810

Modulated RF

80
8.0
7.5
7.0
6.5
6.00Flat RF

345Time [μsec]
peak energy

67TRIODE--TYPE RF GUN
TRIODE
conventional
systemtriodesystemgridcathodecathode1stcell200
4th cell

150
100

3 d cell
3rdll50

2nd cell

Accelerating
Field
Decelerating
Field

1st cell002

Back-bombardment

4Phase [π rad]

68200
150

10100
50002

Axial Distance [mmm]5th cellAxial Dista
Aance Z [mmm]Axial DistaAance Z [mmm]1stcell

8

Accelerating
Field

6

Decelerating
Field4

1st cellcell
1stCathodeCathode
GridGrid204 rad]66880.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0[π 0.2Phase 0.0
rad0.4] Phase[π rad]EMITTANCE MEASUREMENT
fluorescentlight

CCD camera
yQ magnet

xe-x’x

Measurement of beam profilechanging the Q-mag. strength
reconstruction of the distribution
with tomography methods

Lzx’

mirrorx’xscreen

Electron density distribution
in phase spacexemittancePhase-space distribution−1⎛1 1⎞θ = tan ⎜⎜ − ⎟⎟⎝L f ⎠m0γv z r02
1
f = 2 =k z 2μ 0 eNIz
−1μ0 ：magnetic permeability
R0 : bore radius
N : no.of turns
m0: electron rest massγ: Lorentz factor
vz ：electron velocity

ORIGINAL

EMITTANCE MEASUREMENT

Tomographic Method
reconstruction ofp
phase-spacepdistribution
ARTML-EM

1st lasing in KU
KU-FEL FACILITY!!
Amplified
Spontaneous
Current Profile

Saturation ofDetector or Amplifier

0.6

1.2

80

1.0

Peak12367±4nm

0.8WIdth34±7nm

60Gain = 5%

Loss = 4%0.4

400.2200.00-0.2
8101214

Time [μs]

16-20
18

Power [a.uu.]

Signal [a.u.]

0.8

100

Current [mACA]

1.0

0.6
0.4
0.2
0.0
12000

12200

12400

12600

Wavelength [nm]FEL Spectrum
Current
Optical power

0.3

0.2

0.2

0.1

0.1
00
05
Time [μs]10Curreent [A]Intensityy [a.u.]03
0.3

Saturation

12800

KU--FEL FUTURE UPGRADES
KU

therionic RF gun

drive laser

d l
dog-legundulator(FIR radiation)

accelerator tube(decelerator)

photocathodepRF gun
undulator(THz radiation)

undulator
undulator(amplifier)(master oscillator)
FEL-Compton X-ray

180°arc

optical cavity

FEL PRJECTS IN JAPANKU--FEL FUTURE UPGRADES
KU

therionic RF gun

drive laser

d l
dog-legundulator(FIR radiation)

accelerator tube
(decelerator)

pphotocathodeRF gunreturn arc

undulator(THz radiation)

undulator
undulator(amplifier)(master oscillator)
FEL-Compton X-ray

180°arcEN
NERGY / MICROOPULSE (μJ)

KU--FEL POWER PER PULSE
KU
KU-FEL
photocathode102

KU-FEL
present101

10010-1

KU-FELnew undulator

OPO110WAVELENGTH (μm)

210

APPLICATION OF FREEFREE-ELECTRON LASER
selective irradiation toDNA etc.
(wavelength, polarization)

wavelength
tunability
variablepolarization

e-introduction of genes
to cells(wavelength)

Free-Electron Laser
FEL

prevention of tooth cavity(wavelength)

generation of clean energy source
fC O
from
H2O andd CO2
clean fuelH
クリーン燃料2

H22(水 素) CO(二 酸化炭素)2②自由電子レーザ①自由電子レーザ

FELFE L

H 2O

H2(水)
OFE L
FEL
H2clean fuelC H 3 OCH
H 3OH

クリーン燃料CO

selectivedesociationofSi-H bonddetection and removal of pollutantsozone layer

recovery ofozone layerozone holestratosphere(メ タノール)
脱酸素触媒
reduction
catalyst

oxidation catalyst
酸素付加触媒（安価な金属／金属酸化物触媒）③自由電子レーザ

FELFE L

tropoospherehigherefficiency
offsolar cells

Isotope separation：C, Si, U （wavelength）
modulation of semiconductor devices （wavelength）
・・・・・・・・・・

supersensitive
detection

wide area

decomposition & removal
flon
greenhousepollutants

Highpower
FEL

distributionof pollutants
factoryNOx, SOx, granular effluent

ATP合成酵素のATP合成酵素のF
F1部分
蛍光分子磁石ATP S
Syntase as a M
Motor PProteini- by the Yoshida & HisaboriLab
東工大
蛍光による一分子回転の観察

CONCEPTUAL SCHEME OF FEL MALDI TOFTOF-MSIR-FEL
giant
i t moleculellDNA, RNA

matrix ion
mM

gridelectrode

MALDI+ion

detector

time-of-flightti
f fli ht analysis
l i(TOF）

giant molecule
protein molecule
DNA,, RNAfragment ions+V

UV laser0matrix ion
mdetector

生存基盤計測フロンティアの基盤整備事業の概要
宇治地区研究所群

ｴﾈﾙｷﾞｰ理工学研究所

化学研究所

光 ネ ギ 複合研究領域
光エネルギー複合研究領域

光量子光源
プラズマエネルギー複合研
究領域

生存基盤計測フロンティア
基盤整備事業

生存圏研究所

バイオエネルギー複合研究領域•2004年度旧エネ研北2号棟の改修による、量子光・加速粒子総合工学研究棟の完成•光量子光源用加速器装置の完成
光量子光源用加速器装置の完成•共同研究 「高速重イオン・自由電子レーザーの融合照射を利用した新学際領域の開拓」を開始

発展

準備状況

量子理工学研究
実験センタ−
国内外大学・研究所
産業界

生存基盤科学高等研究院
・生存基盤科学高等研究院組織のさきがけ
・生存基盤計測・診断科学の創成に寄与
・生存基盤計測・診断産業の萌芽育成,
生存基盤計測 診断分野の研究者育成
・生存基盤計測・診断分野の研究者育成、社会人教育
・光量子科学への寄与

防災研究所「生存基盤科学」の創成

図１

ACTIVE CREATION OF ENERGY LEVELS
radiation from an atom (laser)+e-e-Energy levels of an atom
i usedisd passeively.
i l
NSN

S

Energy levels arecreatedd actively.
i lNNewQ
QuantumtR
Radiationdi tiradiationfrom an undulatore-NEW QUANTUM RADIATION SOURCES

LIGHT SOURCES
Synchrotron Radiation
Free-Electron Lasers (FEL)FEL Oscillators
SASE FELs

Energy Recovery Linac (ERL) Light Sources
Energy-Recovery
FELs
X
X-ray
S
Sources
Electron Coolers
Electron Ion Colliders
Electron-Ion

CONCEPTUAL SCHEME OF SASE
LASER
LASER

Magnetic
fieldElectron bunch
MIRROR

Force

Bending magnet
Bunching

Electriccurrent

ACCELERATOR
Bending magnet
Electron bunch
LASER
MIRRORDUNRTOAUL32major
major elements
elementsofFELof SASE
FEL
FEL device
deviceOptical cavity
Electronbeam
Electron beam

SASE PROJECTS

http://www xfel spring8 or jp/cband/e/SCSS htm#Milestone
http://www-xfel.spring8.or.jp/cband/e/SCSS.htm#MilestoneCHALLENGES FOR SASE
ELECTRON BEAM
very low emittance of electron beam

λε<4πhigh-current guns
photocathodelifetime
RF gunε = 0.2
0 2 nm · rad forf λ = 3 nm
εn = 0.4 μm · rad for λ = 3 nm @ 1 GeV

thermionic
emittance
DC guncurrent-dependent effects
BBU, CSR , HOM, halo problem, space charge, wake fields
bunch compression
magnetic, RF
tolerance on trajectories
BPMs, magnet alignment, stable stands, halo problem

CHALLENGES FOR SASE
UNDULATOR
tolerance on K values
1.5 x 10-4 = 50-μm vertical misalignment
radiation damage to undulators

RADIATION
stability and reliability
short pulse

1~3 fstiming jitter
shot-to-shot instability
number of beamlines
And manyy moreCHALLENGES FOR ERLELECTRON BEAM
very low emittance of electron beamemittance growth @ merger, etc.
high-current guns
photocathodelifetime
RF gunthermionicemittanceDC guncurrent-dependent effects
BBU, CSR
CS , HOM,
O halo problem, space charge, wake fifields,limitation of energy gain?
bbunchh compression
imagnetic, RFtolerance on trajectories
non-destructive BPMs, magnet alignment,
stable stands

And many more

COMPARISON OF LIGHT SOURCESSR

ERL (SR)SASE

2-8 GeV

1-10 GeV

2-15 GeV

micropulse width 30 – 100 ps

10 fs – 1 ps

10 fs – 1 ps

emittance

1-20 nm (H)
0 1 – 1 nm (V)0.1

0.1 - 1 nm

0.02 – 0.2 nm

repetition rate

10 – 500 Mpps

10 -1000 Mpps

10 – 500 pps

av.
av brilliance

0 01 – 10 × 1020
0.01
ph /s/s/.1%/mm.1%/mm2/mrad2

1022 -1023
ph /s/s/.1%/mm.1%/mm2/mrad2

1022 -1026
ph /s/s/.1%/mm.1%/mm2/mrad2

peak brilliance1022 -1023
ph /s/s/.1%/mm.1%/mm2/mrad2

1025 -1026
ph /s/s/.1%/mm.1%/mm2/mrad2

1033 -1034
ph /s/s/.1%/mm.1%/mm2/mrad2

no. of beamlines

many

many

1 – 10energy

COMPARISON OF LIGHT SOURCESSRERL (SR)SASEelectronbeam

now available

low emittance
CSR, HOM, wakevery high stability
emittance growth atmergersspace charge (energygain)
i )

very
y low emittance
CSR, HOM, wakevery high stability

undulators

now available

now available

very longvery
y highg precisionpradiation

now available
stablemanybeamlines

high av. flux

high peak brillianceshot--toshot
to-shot instability
small
ll no. off beamlines
blicompetition wt. X
X--raylasers

SR + FEL
Compatible

many beamlines
bli

ERL + SASE compatible?

自分（達）は何をやりたいか？
そのためには何が必要か？
失敗を喜んで認める
失敗から回復する
いずれは必ず成功するという信念
成功しそうな時の確認
ライヴ ルとの競争と協調
ライヴァルとの競争と協調
利用者との議論と協調
集中拠点と分散拠点

さまざまな量子放射源
総合的，境際的な視点
加速器技術の重要性

Thank you for your attention.

I have to thank many colleagues
colleagues.
Electrotechnical Laboratoryy ((AIST))
Eectron Accelerator Group
Takio TOMIMASU (kyushu U.), Kawakatsu YAMADA,Norihiro SEI,SEI Hideaki OHGAKI (kyoto(k t UU.),)
Suguru SUGIYAMA (retired), Tsutomu NOGUCHI (retired),Takeshi NAKAMURA (JASRI), Tomohisa Mikado (late),
Hi
Hiroyukiki TOYOKAWA,TOYOKAWA Ryoichi
R i hi SUZUKI,SUZUKI Toshiyuki
T hi ki OHDAIRA

Collaboration with
Kawasaki Heavy Industries Co.
M. KAWAI, M. YOKOYAMA, S. HAMADA, A. IWATA, K. OWAKI
Mitsubishi Electric Co.
Co
N. SATO, H. USAMI
Sumitomo Electric Industries Co.
H TAKADAH.
TAKADA, Y
Y. TSUTSUITSUTSUI, ⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅SR Users⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅I have to thank many colleagues
colleagues.
KU FEL GroupKU-FEL
Institute of Advanced Energy, Kyoto University
Hideaki OHGAKI, Toshiteru KII, Kai MASUDA,Ki
Kiyoshihi YOSHIKAWA
GRADUATE STUDENTS
Quantum Science & Engineering Center,Center Graduate Schoolof Engineering, Kyoto University
Koji YOSHIDA

Collaborators fromNational Institute of Advanced Industrial Science andT ch lTechnologyiFEL, Graduate School of Engineering, Osaka University
Nissin Electric Co.
FEL Users⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅⋅