development of lcs x-rays and coherent thz sources on the … · 2013. 7. 28. · positron beam...

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China-Korea-Japan Joint Workshop on electron/photon sources and applications, Dec. 2-3, 2010@SINAP

R. Kuroda1 H. Toyokawa1, E. Yamaguchi1, M. Kumaki4, M. Yasumoto1, H. Ikeura-sekiguchi1, E. Miura1, K. Yamada1, F. Sakai2, K. Mori3

1National Institute of Advanced Industrial Science and Technology (AIST), Japan2Sumitomo Heavy Industries, Ltd (SHI), Japan

3Ibaraki Prefectural University of Health Sciences, Japan4 RISE, Waseda University, Japan

Development of LCS XDevelopment of LCS X--rays and coherent THz sources rays and coherent THz sources on the basis of Son the basis of S--band compact band compact linaclinac at AISTat AIST

Contents

1. Introduction of S-band compact linac at AIST2. Laser Compton scattering (LCS) X-ray source and its applications3. Coherent THz radiation source and its applications4. Summary

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TsukubaKEK

JAPAN

Where ?Where ?

AISTNational Institute of Advanced Industrial Science and TechnologyAIST is one of the largest national research institutions

in Japan. About 2,500 Ph. D researchers are working for cutting-edge R&D in wide research fields such as life science, information technology, environment technology, nanotechnology, Geological survey, Measurement Technology …etc.

Accelerator group is very small group about 10 peoples.

(located near KEK in Tsukuba, Japan)(located near KEK in Tsukuba, Japan)

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FEL

Compact SCompact S--band band linaclinac

Storage ring TERASLaser Compton gamma-ray experiment

(NRF, gamma-ray imaging)

Storage ring NIJI-IV

Positron Beam linePositron Beam line

Laser Compton X-ray sourceCoherent THz radiation source

Accelerator Facility at AISTAccelerator Facility at AIST(nearby KEK in Tsukuba)(nearby KEK in Tsukuba)

Introduction

Focus!Focus!

400 MeV linac(since 1978)

•Positron annihilation lifetime spectroscopy

New

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RF gun & 3m LINAC(1.5mRF gun & 3m LINAC(1.5m××2)2)

KlystronKlystron

Ti:Sa LaserTi:Sa Laser

UV LaserUV Laser

10 m

Energy：~42 MeVBunch charge：1 – 3 nCBunch length: sub ps - 3ps (1σ) Bunch number: 1 – 100

(Bunch spacing: 12.6 ns )Repetition rage：10Hz - 50Hz

Electron beam

S-band compact linac facility @AIST

ApplicationApplicationspacespace

e- beam

All components are installed in one middle size room (10m×10m)

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◎Laser Compton scattering X-ray source

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X-ray wave length

)cos1(2)2/1(

2

2220

φγθγλλ

−++

≅K

IcmeAK e 092

0 1085.0/ λ−×≈=

Laser Undulator Radiation

( )( ) 2

0

0

0

)cos(1cos1

cos1

cmE

EE

γφθθβ

φβ

+++−

+=

Scattered X-ray energy

φ

θ

Laser

Electron beam

γ m0c2

X-ray (λ (E))

(λ0 [µm] (E0[eV]), I [W/cm2] )High Power Laser

Scattered X-ray

High Energy Electron Beam

Interaction between high energy electron beam and high power laser

LCS XLCS X--ray sourceray source•Short pulse•Energy tunability•Quasi- monochromatic•Small source size•Good directivity •Good polarization•Compact system …etc

Principle of Laser Compton Scattering (LCS)

Many benefits!

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Application SpaceApplication SpaceLaser Compton Scattering (LCS) hard X-ray Source at AIST

Cs-Te

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AOM1m

0.7m

AMP

Pre-AMP

PCConversion Crystal

Oscillator

UV laser statusAll solid-state and compactPulse energy: 10 µJ × 100 pulse/ macro pulsePulse width : 10ps(FWHM)Pulse number: 1 – 100 pulses

1m

We can arbitrary generate a single pulse and multi pulses (100 pulses).

Compact UV laser system for rf gun

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BNL-typeRF-gun

Compact evaporation chamber

Cathode plug(Mo)

Compact Cs-Te cathode

load-lock system

Delivering unit

(in Collaborating with KEK and Waseda Univ.)

Energy：4 MeV (40MeV at linac out)Bunch charge：1 nCBunch length: 3 ps (rms) Bunch number: 1 – 100

(Bunch spacing: 12.6 ns )Repetition rate：10Hz (Max 50Hz)

Electron beam status at rf gun out

Cs-Te photocathode rf gun

New rf gun

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Q-sw

itched

Nd: YA

G las

er

10H

z

Q-sw

itched

Nd: YA

G las

er

50H

z

λ/2

PBS

Ti: S

A

PC

PB

S

AP

G

Stretcher

PB

S

PB

SFR

G

G

OSC.Q-rayQ-ray10Hz

7W~9W Regen

Pre. AMP.

Main AMP.

Compressor

40mJ

300mJ

7W (700mJ)

200 ps

Pulse pick up @10 Hz

60 mJ

200 mJ

Laser StatusWavelength: 800 nmPulse energy: 100-140 mJPulse width: 100 fs(FWHM)

10Hz

4W

PD 79.3MHz → PLL circuit

SESAM(PZT)

OC 5W MillenniaOSC.

79.3 MHz

200 mW

50 fs

Vacuum pipe

1200gr/mm21200gr/mm2

12480gr/mm2

Collision Laser (CPA Ti:Sa laser) for single collision LCS

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fiber

Klystron

ps-laser

To rf gun laser

fs-laser

To CPA Ti:Sa laser system

Directional Coupler

Master Oscillator2856MHz

PD

2856MHz

To gun & Linacs

79.3 MHz

79.3 MHz

2856 MHzDrift compensator

Timingstabilizer

36th harmonics(2856MHz)

Timingstabilizer

Drift compensator

・Two lasers are synchronized to the master with 36th harmonics of their mode-lock frequencies.・Relative timing jitter between the master and the laser is < 10fs.

(F. Sakai, Proceedings of SPIE, 5194, 149-156 (2003)

(Drift <1ps)

This synchronization system has been accomplished in order to generate 150 fs LCS X-ray in FESTA project in collaborating with SHI.

Timing synchronization system (Low-jitter)

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0.2%Energy spread

40/30 µmBeam size (σx/σy)3 psBunch length (rms)1 nCBunch charge/bunch

20 ~ 42 MeVElectron EnergyTW TW Ti:SaTi:Sa Laser beam (CPA)Laser beam (CPA)

30 µmBeam size (σx/σy)100 fsPulse width (FWHM)

140 mJEnergy/pulse800 nmWave length

Electron beamElectron beam

3 ps

150 fs

Pulse width (rms)

~106 /s (max) @10Hz~20 keV90

~107 /s (max) @10Hz10 ~ 40 keV(tunable)165

Number of PhotonsMax photon energy

Collision angle (φ)

XX--ray beamray beamApplication to biological and medical research

in-line phase contrast imaging, K-edge imaging(because of quite small size of X-ray source about 30~40 µm)

Present beam status (single pulse collision – single pulse X-ray)

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1 Experimental results of in-line phase contrast imaging

2 Experimental results of K-edge imaging

Applications to biological & medical uses

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Sample 1 : lumbar vertebra of ratSample 2 : Hind limbs of Ovariectomized mouse (OVX*)

and Normal mouse *OVX mouse is female mouse whose ovary is extracted

and it forcibly make osteoporosis (bone disease).

X-ray energy : 30 keV

Detector : Blue Imaging Plate (IP)

Exposure Time: 30 min (18000pulse)

2m1m0~750mm

Be Window (30mmφ)SampleIPLaser Compton Scattering

X-ray Source

Experimental SetupIn Collaborating with Ibaraki Prefectural University of Health Sciences in Japan

H. Ikeura-Sekiguxhi, R. Kuroda et al., APL 92，131107 (2008)K. Yamada, R. Kuroda et al., NIMA (2009)(accepted)

InIn--line phase contrast imaging for biological applicationline phase contrast imaging for biological application

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Micro- focus X-ray tube(80kV)

Results of in-line phase contrast imaging①lumbar vertebra of rat ②Hind limbs of normal and OVX mouses

5mm

Normal

LCS X-ray source can realize more contrast enhancement than X-ray tube!

Comparison

Contrast enhancement

OVX

Absorption PhaseContrast

Distance between sample and detector40mm 750 mm

We can observe the bone erosion of OVX mousewhich is the initial symptom of osteoporosis !

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Samples: Sample1: Resolution chartSample2: Rabbit ears with iodinated contrast media (K-edge:33.17 keV)

Exposure time of 1 frame: 3ps (rms) @ single shot, 30 ps @10 shot

Detector: Real time camera (HARP) with X-ray II

2m

Be Window (30mmφ)

Specimen

Detector

Laser Compton X-ray Source

K. Yamada et al., ICFA Workshop "Compton Sources for X/γ Rays: Physics and Applications“, Italy, September 2008

In Collaborating with Prof. Mori Group at National Cardiovascular Center in Japanin order to research the new diagnosis for the initial symptom of the blood vessel disease

(such as diabetes)

K. Yamada, R. Kuroda et al., NIM A 608, pp. S7-S10 (2009)

K-edge imaging for angiography

using laser Compton X-ray source @AIST

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30 frame/sec

(X-ray is 10Hz)

1 frame: 3ps single shot X-ray

1 frame/sec

1 frame: 30 ps X-ray (10 shot)

1 frame/sec

1 frame: 30 ps X-ray (10 shot)

Real time imaging with picosecond (ps) X-ray pulse

Rabbit ear (iodine)Resolution chart Resolution chart

Single shot：250μm

10 shots ：125μmResolution Achieved spatial resolution of

single shot imaging is 480µm !(System optimization is not completed)

10mm

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Cavity length：7.6 m @79.3MHzLaser average energy: 100 mJLaser pulse number : 100Stored laser power： 10 J

100 electron bunches ×100 laser pulses

→ 100 X-ray pulses

Electron beam is ready

Not super cavityRegenerative Amp. type laser cavity!

synchronized

Multi-Collision Laser Compton Scattering (Multi-LCS)

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5 × 109 /sTotal photon yield

10 HzRepetition rate

5 × 106 /pulseLCS photon number

38 keVMaximum LCS X-ray energy

170 degCollision angle

10 ps (FWHM)Laser pulse width

38 µmLaser spot size (σx, σy)

100 mJ/pulseAverage laser energy

10 J / 100 pulseStored laser power

800 nmLaser wavelength

10 ps (FWHM)Electron bunch length

40 µmElectron spot size (σx, σy)

100Bunch number

1 nC/bunchElectron charge

40 MeVElectron energy

Calculation of hard X-ray yield using Multi-LCSParameters for calculation

The yield of Multi-LCS hard X-ray on this design was estimated to be about 5 × 109 /s.

Under development

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◎Coherent THz radiation source based on S-band compact electron linac

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Cs2Te photocathode RF gunAchromatic arc.

（Bunch compressor）

S-band linac

fs electron bunch

THz CSR pulse

・THz-Time Domain Spectroscopy ・THz imaging

The high power THz source

Ti:Sa fs-laser

Design values

THz freq.: 0.1 ~ 2 THzPulse energy: >10 nJPeak power: >1 kW

Electron energy：40 MeVBunch Charge/bunch ：1 nC ～ 2 nCBunch length : 300 fs ~ 3 ps (1σ)Bunch number：1～100バンチRep. rate：10Hz ~ 50HzAverage current： 10μA (2nC、100、50Hz)

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Ultra short electron bunch generation

S-band linac

S-band compact electron linacLaser photocathode rf gun

Energy distribution

Achromatic arc section

E<E0

E=E0

E>E0

8m

Achromatic arc section

E>E0

E<E0

time

Energy

◎Bunch compression using achromatic arc

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Generation of THz coherent synchrotron radiation (CSR)

Generation of ultra-short electron bunch

& THz CSR

W-band detector(WiseWave FAS-10SF-01)

Frequency range： around 0.1THz0.075~0.11THz (2.7~4.0mm)

Aperture ：1mm(H) X 2mm(V)Sensitivity：500mV / 1mW

Bunch length monitor

Coherent radiation

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◎ THz scanning transmission imagingCoherent THz pulse

WR-10 wave guide

THz detector

sampleXY stage

XY StageParabolic antenna

(0.1, 0.3 THz)

JapaneseTrain card

@0.1THz

Sample position

DetectorWave guide

antenna

@0.3THz

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2mm2mm

○liquid bond⇒ bonded by removing water ⇒ high polymer

Polypropylene plate after 1 week

Optical imageTHz image

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© C.S/JR東日本/D

○ Sample3 Inside of Envelope

Other Imaging results○ Sample 1 Vegetable

5 cm

14 hourslater

0 hour

10 hourslater

○ Sample 2 Biological imaging (pork)

Envelope

9cm

Protein

fat

3 cm

○ Sample 4 Credit Card

@0.3THzCredit card with

IC chip

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Off-axis parabolic mirror

Sample

EO crystal（ZnTe）

THz-pulse

Ti:Sa laser800nm, 50fs

Optical delay stage

Polarizer

Polarizer

1/4λplate

PD

PD

0.1~2 THz, 700fs

THz-TDS system design

Quartz window (z-cut single crystal)

Time domain（THz temporal distribution）

Freq. domain（Spectrum

distribution）

Fourier transform

Under development!

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Summary

X-ray energy : 12 - 40keV (electron beam energy: 42MeV)Photon number : >107 photos/s @ 10Hz

In near future, we will generate more than 109 /s via Multi-LCS for biological and medical applications.

The coherent THz radiation has been observed on S-band compact electron linac at AIST. THz scanning transmission imaging has been successfully demonstrated for many samples.In near future, we will finish set up of the high power THz-TDS system

and start the investigation of the un-researched materials in the frequency range of 0.1 – 2 THz.

application to medical and biological imaging was started.

Laser Compton scattering X-ray source based on S-band linac

Coherent THz radiation source based on S-band linac

Thank you

for your attention !

development of lcs x-rays and coherent thz sources on the … · 2013. 7. 28. · positron beam...

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