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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 [email protected]
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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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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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)