1

Undulator Undulator AAlignment for lignment for the SPringthe SPring--8 XFEL8 XFEL

Makina Yabashi, Takashi Tanaka, Sakuo Matsui, Hirokazu Maesaka, Yuji Otake, Hideo Kitamura,

Tsumoru Shintake, Tetsuya Ishikawa, Noritaka Kumagai yabashi@spring8.or.jp

IWAA08: The 10th International Workshop on Accelerator Alignment Jan. 12 2008 @KEK

RIKEN XFEL Project Head Office

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AcknowledgementAcknowledgementRIKEN & JASRI Joint Project for XFEL : Takao Asaka, Yoshihiro Asano, Hitoshi Baba, Teruhiko Bizen, Hiroyasu Ego, Toru Fukui, Shunji Goto, Hirohumi Hanaki, Toru Hara, Takaki Hatsui, Atsushi Higashiya, Toko Hirono, Naoyasu Hosoda, Takahiro Inagaki Shinobu Inoue, Miho Ishii, Toshiro Itoga, Hiroaki Kimura, Masanobu Kitamura ,Satoru Kojima , Togo Kudo, Hirokazu Maesaka , Xavier Marechal, Sakuo Matsui, Hiroshi Matsumoto (KEK), Tomohiro Matsushita, MItsuru Nagasono, Haruhiko Ohashi, Toru Ohata, Takashi Ohshima, Kazuyuki Onoe(Alvac), Yuji Otake, Tatsuyuki Sakurai, Takamitsu Seike, Katsutoshi Shirasawa, Shinsuke Suzuki, Kazuhiko Tahara, Tetsuya Takagi, Sunao Takahashi, Takeo Takashima, Masao Takeuchi, Hitoshi Tanaka, Ryotaro Tanaka, Takashi Tanaka, Yoshihito Tanaka, Shingo Taniguchi, Takanori Tanikawa, Tadashi Togashi, Kazuaki Togawa, Hiro Tomizawa, Shukui Wu, Akihiro Yamashita, Kenichi Yanagida, Chao Zhang , Tsumoru Shintake, Noritaka Kumagai, Tetsuya Ishikawa, Hideo Kitamura, ･･･

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E-XFEL

LCLS

SPring-8

4

5 km

5

SPringSPring--8 site8 site

SPring-8 (1436 m) since 1997

XFEL (700 m)from ~2011

CG

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JapanJapan’’s XFEL: s XFEL: SPringSPring--8 Compact SASE Source (SCSS) Concept8 Compact SASE Source (SCSS) Concept

SR-2準備室準備室

測定

２セミナー室

ＷＣ

搬入室冷却機室

準備室

測定

３

倉庫 測定

１

機械室（計14 4席）

空調機械室 電気室準備室準備室測定

４

測定

５

共通室共通室玄関ホール

Total length of 700 m

Use of short-period undulator

Suppression of acceleration energy 2

2 12 2magnet

photonKλ

λγ

⎛ ⎞= +⎜ ⎟

⎝ ⎠

Use of high-gradient linac+

=

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Project ScheduleProject Schedule

Linac Bldg.

Undulator Bldg.

Exp. Hall

Injector

Accelerator I

Accelerator II

Beamlines

EBT

FY2006 2007 2008 2009 2010Dr. Kumagai

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Undulator hallUndulator hall

EmbankmentWeathering bedrockBedrockReplacement by excavation with crusher stone

Accelerator sectionUndulator section

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Undulator alignmentUndulator alignment

~ 100m

磁石取付磁石 磁石取付磁石

50 40

5220

磁石取付磁石 磁石取付磁石

50 40

5220

磁石取付磁石 磁石取付磁石

50 40

5220

H- Co rd ie rit e8 00 x70 0- V4 5

4 10

1 007 5 8 7 1 608 7 7 5

8 00

2 36 1 10

Q-D-V44

11 10

930

H- Co rd ie rit e8 00 x70 0- V4 5

Q-D-V444 10

1 007 5 8 7 1 608 7 7 5

8 00

2 36 1 10

1 1 10

930

H- Co rd ie rit e8 00 x70 0- V4 5

4 38

7 27 5 1 15 1 608 7 7 52 36 1 10

Q-D-V448 00

11 10

930

PM

-mo

nito

r

rf-B

PM

ST-

BL

3-15

(D)

ST-

BL

3-14

(D)

Q-m

ag-

D

Pha

seSh

ifter

CT

-mon

itor

rf-B

PM

ST-

BL

3-19

(D)

ST-

BL

3-18

(D)

Q-m

ag-

D

Pha

seSh

ifter

GV

ST-

BL

3-13

(D)

Q-m

ag-

D

GV

rf-B

PM

ST-

BL

3-17

(D)

ST-

BL

3-16

(D)

Q-m

ag-

D

Pha

seSh

ifter

5 m ×18 segments

Segmented undulators should work as if they were single module !!

overlap of e-beam & p-beam

Dr. Kitamura

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CriteriaCriteria1. Straightness of trajectory: θC < 0.6 urad (LθC <3 um)2. Magnetic field deviation: ΔK/K < 2e−4

T. Tanaka, SIMPLEX

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Different approachesDifferent approaches

E-beam:Iris-coupled BPM (~ a few 10 um)

P-beam:Spatial profile of monochromatic x-rays ( ~ a few um)Spectrometer (Magnetic field deviation: 1e-4)

It is difficult to foresee the initial status (stability, reproducibility ...)Multiple approaches should be prepared

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Alignment of BPMsAlignment of BPMs

ID1 ID2BPM1 BPM2 BPM3

STEP 1: Align BPMs to straight line

STEP 2: Steer e-beam to the BPM origins

STEP 0: Initial condition

e-beam

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IrisIris--coupled BPMcoupled BPM

Problem: Large diameter of laser iris (> 5 mm) is required for suppressing diffractionShorter wavelength radiation

Dr. Shintake

SCSS CDR 2005

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Shorter wavelength sourceShorter wavelength source

1. UV: e.g., He-Cd laser

2. X-rays: Alignment undulatorYang & Friedsam, IWAA 2006

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Alignment undulatorAlignment undulator

AL-ID1 ID#1Iris U

e-beam, to dump

Iris 1 ID#N Iris N

zU =30 m zN =35 ~ 145 m

ID#18 Iris D

zD

=150 m m

X-CCD

zCCD

=250 m m

p-beam

Distance from AL-ID

-100 0 1000

0.01

0.02

0.03

X offset (μm)

Inte

nsity

Rat

io (F

CC

D/F

U) z1=35 m

z18=145 m Iris diameter: 100 umSensitivity: ~ 10 um

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-20 -10 0 10 200

0.5

1

1.5[×1011]

Y-angle (μrad)

Inte

nsity

(a.u

.)

10010 eV 9996.2 eV 9900 eV

PP--beam based alignmentbeam based alignmentUse of spontaneous radiation with monochromator

ST-Mag

ID1 ID2

Requirement/FWHM = 0.6 urad / 8 urad = 8 %

9960 9980 10000 10020 100400

0.5

1

[×105]

Photon energy (eV)

Inte

nsity

(pho

tons

/0.3

nC

/eV

/3 u

rads

q)

Mono

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Separation of profilesSeparation of profiles

ST-Mag

ID1 ID2

ST-Mag

ID1 ID2Double-crystalmonochromator

Thin-crystalmonochromator

Double-crystalmonochromator

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KK--value adjustment (SLACvalue adjustment (SLAC’’s proposal)s proposal)

Scan of crystal monochromator

Intensity monitor

9960 9980 10000 10020 100400

500

1000

σE=0.03 % K=2.18 K=2.182 average

Inte

nsity

(pho

tons

/eV

/0.3

nC

/3 u

rads

q/pl

s) ΔK=1e-3

Problem: sensitive to e-beam jitter (charge, energy, position, angle)in the reconstruction process

ID1 ID2Mono

Shot-by-shot recording of :E-beam energy, chargeP-beam energy, intensity

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Measurement of eMeasurement of e--beam parameters (SLAC)beam parameters (SLAC)

!!!

!!!

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SingleSingle--shot spectrometershot spectrometer

Grating spectrometer:

Low efficiency in hard x-ray regime:Multilayer grating ?

Shigemasa & Yabashi, JSSRR, 2006

Ishino, Koike et al, Appl. Opt. 2006

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SingleSingle--shot spectrometershot spectrometer

/ cot BE E θΔ = Ω

Si111: 1 eV @ =10 keV( / 1e-4)

E EE E

Δ =Δ =

Single-shot detection

PSDID1 ID2Spectrometer

Yabashi et al, PRL 2006

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Summary: Requirement for machine & undulatorSummary: Requirement for machine & undulatorTrajectory alignment K-value adjustment

Charge ~ 0.3 nC As large as possible

Projected emittance ≤

5 πmm.mrad ??Bunch compression unnecessary unnecessary

Energy spread σE (along bunch)

~ 1e-3 ≤

3e-4

Energy jitter (pulse-to- pulse)

~ 1e-3 ~ 1e-3

Angular jitter (pulse-to- pulse)

< 10 μrad (1 mm / 100 m) < < 3 μrad

Preliminary positioning accuracy of BPM

~ 50 μm

BPM resolution & stability (single shot)

<< 4 μm

e-beam kick inside undulator

<< 0.6 μrad ?? (Larger value may be tolerable)

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SummarySummary

Trajectory:Course tuning (~ 10 um): iris-coupled BPM,

alignment undulatorFine tuning (~ um): Spontaneous radiation with

monochromators, thin-crystal monochromator

Magnetic field:Single-shot spectrometerImposes special condition for e-beam operation

2D-detectorHigh-efficiency, moderate rep. rate (~1 Hz), resolution (~50 um)