status of the erl project in japan
DESCRIPTION
Status of the ERL Project in Japan. Norio Nakamura for the ERL Collaboration Team. Institute for Solid State Physics(ISSP), University of Tokyo . ERL collaboration team. High Energy Accelerator Research Organization (KEK) - PowerPoint PPT PresentationTRANSCRIPT
Status of the ERL Project in Japan
Norio Nakamurafor the ERL Collaboration Team
Institute for Solid State Physics(ISSP), University of Tokyo
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
High Energy Accelerator Research Organization (KEK)M. Akemoto, T. Aoto, D. Arakawa, S. Asaoka, A. Enomoto, S. Fukuda, K. Furukawa, T. Furuya, K. Haga, K. Hara, K. Harada, T. Honda, Y. Honda, T. Honma, T. Honma, K. Hosoyama, M. Isawa, E. Kako, T. Kasuga, H. Katagiri, H. Kawata, Y. Kobayashi, Y. Kojima, T. Matsumoto, H. Matsushita, S. Michizono, T. Mitsuhashi, T. Miura, T. Miyajima, H. Miyauchi, S. Nagahashi, H. Nakai, H. Nakajima, E. Nakamura, K. Nakanishi, K. Nakao, T. Nogami, S. Noguchi, S. Nozawa, T. Obina, S. Ohsawa, T. Ozaki, C. Pak, H. Sakai, S. Sakanaka, H. Sasaki, Y. Sato, K. Satoh, M. Satoh, T. Shidara, M. Shimada, T. Shioya, T. Shishido, T. Suwada, T. Takahashi, R. Takai, T. Takenaka, Y. Tanimoto, M. Tobiyama, K. Tsuchiya, T. Uchiyama, A. Ueda, K. Umemori, K. Watanabe, M. Yamamoto, Y. Yamamoto, S. Yamamoto, Y. Yano, M. YoshidaJapan Atomic Energy Agency (JAEA)R. Hajima, R. Nagai, N. Nishimori, M. SawamuraInstitute for Solid State Physics (ISSP), University of TokyoN. Nakamura, I Itoh, H. Kudoh, T. Shibuya, K. Shinoe, H. TakakiUVSOR, Institute for Molecular ScienceM. Katoh, M. AdachiHiroshima UniversityM. Kuriki, H. Iijima, S. MatsubaNagoya UniversityY. Takeda, T. Nakanishi, M. Kuwahara, T. Ujihara, M. OkumiNational Institute of Advanced Industrial Science and Technology (AIST)D. Yoshitomi, K. TorizukaJASRI/SPring-8H. Hanaki
ERL collaboration team
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Outline
1. Overview of the ERL project2. R&D status
- Gun and SC cavities3. Compact ERL
- Design study and building4. Summary
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
ERL Project
ParameterBeam energy 5 GeV
Average current 10 - 100 mA
Normalized emittance 0.1 - 1 mm·mrad
Energy spread (rms) (0.5 - 2) 10-4
Bunch length (rms) 1 - 3 ps (usual mode)~ 100 fs (bunch compression)
RF frequency 1.3 GHz
Parameters of the 5-GeV ERL
ParameterSpectral range 30 eV - 30 keV
Average brilliance from insertion devices
1021 - 1023 ph/s/mm2/mrad2/0.1%bw
Average flux > 1016 phs/s/0.1%bw
Number of ID’s 20 - 30
Parameters of the light sources
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
5GeV ERL
Compact ERL(cERL)
KEK site
Compatibility of ERL and XFEL-O
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
SC cavities shared by introducing an orbit bump of a half RF wavelength– 5-GeV ERL beam 2 times accelerated with the orbit bump off– 7.5-GeV XFEL-O beam 3 times accelerated with the orbit bump on
XFEL-O
(a) 5-GeV ERL
(b) 7.5-GeV XFEL-O
Bunch train and pulsed bump for hybrid operation
Orbit Bump Section
Possible scheme for compatibility of 2-loop ERL and XFEL-O
2-loop ERL
SC cavities
XFEL-O
2-loop ERL
500-kV DC Photocathode Gun
500-kV gun with a segmented insulator guard ring against field emission
field emission
ceramicguard ring
HV terminal
support rod
cathode
anode
Segmented insulator with guard rings employed to mitigate field emission.
e-beam
gun chamber
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratorysegmented insulator
HV Testing of 500-kV DC Gun
500 kV for 8 hours without any dischargeField distribution of the 500-kV gun
Talk by N. Nishimori for more details.
6.8 MV/m on guard rings
1200
1000
800
600
400
200
0
-200
0 200 400 600
HV terminal
gun chamber
8.3 MV/m on support rod
14.3 MV/m on nose of support rod
segmented insulator
radius (mm)
heig
ht (m
m)
(HV testing done without a cathode electrode)
R. Nagai et al., to be published in Rev. Sci. Instr.
current through resistors
radiation level is within the background.no clear evidence for dark current.
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Test Injector Beamline
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Laser system
2nd 500 kV guntest area
1st solenoid2nd solenoid
3rd solenoid 4th solenoid
1st view screen2nd view screen
1st slit(vertical)
1st slit(horizontal) 2nd slit
(vertical)
2nd slit(horizontal)
The same layout as cERL injector
Beam diagnostic line (emittance & bunch length measurements)
Beam dump line
3rd view screen 4th view screen
5th view screen
deflector
• Test injector beamline set up in the PF-AR-south building.• Purposes : To gain operation experience of the low energy beam. To evaluate performance of the guns by measuring the
emittance and bunch length with a diagnostic line. To develop the 2nd 500-kV gun and the injector line used
at cERL. 200 kV gunTest beamline
Talk by T. Miyajima for more details.
Laser room
200kV Gun2nd 500kV Guntest area
Beam Dump
buncher
Bending magnet
Drive Laser System
Yb fiber oscillator and amplifier developed by AIST and ISSP
Yb fiber laser systemat KEK
1.3 GHz, 515 nm, 20 ps, 1.5 W (10mA operation) Yb fiber laser oscillator (Cornell type) + fiber amplifier Second harmonic generation (SHG): 100mW output achieved Construction of pulse shaping system and transport to the gun Ti:sapphire psec laser for high-charge and short bunch tests
1.3 GHz, 800nm(tunable), 20 ps, 15 W (100mA operation) Yb fiber laser oscillators (EO modulation & linear cavity types) 10W + 200W fiber amplifiers SHG and OPA for tunable wavelength around 800 nm
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Laser system for gun commissioning at KEK
Development of system components by AIST and ISSP
Ti:sapphire laser system at KEK
oscillator 10W amplifier
Basic cavity Parameters for Injector
HOM couplersTwo input ports
Injector SC Cavities (1)
・ Three 2-cell cavities for 5 – 10 MeV acceleration of 100 mA beam
・ Accelerating field : 15 MV/m・ Two input couplers for each cavity・ Four or five HOM couplers (loop
and antenna types) for each cavity
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Prototype 2-cell cavity
Design of HOM couplersK. Watanabe, S. Noguchi, E. Kako et al., Proc. of SRF09, Berlin, 2009.
Injector SC Cavities (2)
Vertical test results of 1st prototype cavity • Maximum accelerating field : 30 MV/m
( 44 MV/m without HOM probes)• Heating of HOM probes for high fields• Stable operation for 11 hours at 15-16 MV/m
Heat-up of HOM probe
30MV/m
1st vertical test (2009 Apr.)
11-hour operation @15-16MV/m
Set-up for a vertical test
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Lack of Liq. He
2nd vertical test (2010 Feb.)
44 MV/m
without pick-up probes of HOM couplers
SC Cavity• Two Input couplers tested in early 2010• 300-kW klystron successfully developed (S. Fukuda et al., 6th Conf. of Particle Acc. Society of Japan, 2009)
• 2nd prototype cavity with 5 HOM couplers fabricated.
• Three real cavities under fabrication• Design of cryomodule almost completed
Cryomodule
Injector SC Cavities (3)
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
5 K80 K
300 K
Target200 kW
CWWarm
Window
Water Cooling
Zo = 41.5
W
Input coupler
300-kW klystron2nd prototype cavitywith 5 HOM couplers
Two input couplers for High Power Test
Main SC Cavities (1)Target and feature of main SC cavity1) Acceleraitng field: 15 MV/m (f=1.3GHz)2) Beam current : 100 (acc.) + 100 (dec.) = 200 mA 3) HOM damping design
Large-aperture iris and beam pipe and HOM absorberEccentric-fluted beam pipe (converter from quadrupole to dipole mode)
Eccentric-fluted beam pipe HOM absorber
Frequency 1.3 GHz
Iris diameter 80 mm
Beam pipe diameter 100/120 mm
Rsh/Q 897 Ω
Ep/Eacc 3.0
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
E-singleC-single
Parameters of main SC cavity
Vertical test
9-cell cavity design
Two type of single-cell cavities Eacc > 20 MV/m achieved for both cavities
C-single E-single
HOM absorber
Main SC Cavities (2)
• Maximum accelerating field : 15-17 MV/m• Accelerating field limited by field emission• A tip found on an iris between 8th and 9th cells Vertical test resumed after polishing the tip
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
8-9 iris(150 °)
X-ray mapping by a rotating mapping system
1cell
2cell
3cell
4cell
5cell
6cell
7cell
8cell
9cell
60.0
15
PI N1
PI N9
PI N18PI N11
PI N27PI N20
PI N36PI N29
PI N45
PI N54PI N47
PI N63PI N56
PI N72PI N65
PI N38
PI N81PI N74
φ 264
345.5
φ 337
φ 235
323
φ 264
346.504
φ 337
φ 235
334
φ 264
346.504
φ 337
φ 235
334
103.9
40
φ 400
φ 268
PI N2
PI N10
PI N19
PI N28
PI N37
PI N46
PI N55
PI N64
PI N73
PI N82
40
φ 400
φ 268
40
φ 400
φ 268
Tip on an iris of the cavity (f : several hudred mm)
2K
4.2K
151050 20 25 30Eacc [MV/m]
1011
1010
109
108
Q0
9-cell cavity
Vertical test
0
360
180
Angle[deg]
Sharp X-ray signal
Broad X-raysignal
Array ofPIN diodes
K. Umemori, T. Furuya et al., SRF09.
• Ceramic windows and bellows of an input coupler fabricated and tested Ceramic window design slightly modified.
• HOM damper prototype with a comb-type RF shield fabricated and HOM absorbers tested.
• Cryomodule design containing two cavities with three HOM dampers in progress.
Main SC Cavities (3)
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Cryomodule
HOM damperPrototypeHOM damperwithout absorberLeft: outsideRight: inside
HOM dampers
Cavities Input couplers
Input coupler
RF powerCold window Warm window
Bellows
Cooling air
Cold window
Warm window
M. Sawamura et al., SRF09. H. Sakai et al., SRF09.
16
Compact ERL
Parameters
Beam energy 35 - 245 MeV
Injection energy 5 - 10 MeV
Average current 10 - 100 mA
Acc. gradient (main linac)
15 MV/m
Normalized emittance
0.1 - 1 mm·mrad
Bunch length(rms)
1 - 3 ps (usual)~ 100 fs (with B.C.)
RF frequency 1.3 GHz
Parameters of the Compact ERL
100 m
Before constructing a large-scale ERL facility, we need to demonstrate the expected ERL performance using key components. Compact ERL
East Counter Hall
Conceptual Design Report published in 2007KEK Report 2007-7/JAEA-Research 2008-032R. Hajima, N. Nakamura, S. Sakanaka, Y. Kobayashi eds.
Injector design for cERL • Injector components of cERL– Photocathode DC gun– Two solenoids – Bunching cavity (Buncher)– Three SC cavities– Five quadrupole magnets– Merger (using three bending magnets)
• Initial Conditions– Electron distribution on cathode: beer-can shape – Initial charge: 80 pC
• Parameters optimization – Generic algorithm– Tracking code GPT– Space charge effects included– No CSR in merger
• Optimization result– Rectangular type gives smaller emittance
than the sector type. – Normalized emittance 0.4 – 0.5 mm mrad for
2 – 3 ps bunch length.
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
(1) Sector type (bending angles : -19, 22, -19 degree)
(2) Rectangular type (bending angles : -16, 16, -16 degree)
Normalized rms emittance0.4 ~ 0.5 mm mrad
Error Analysis of cERL Injector
Talk by T. Miyajima for more details.
An example of error analysis results(Arrival time offset vs RF amplitude error)
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Gun ripple < 0.1 %, RF amplitude error < 0.1 %, RF phase error < 0.1 °
Amplitude error in RF cavity
Phase error in RF cavity
Summary of error analysis results
Optics Design of 1-loop cERL
Optics functions(in high-current and low-emittance modes)
Beam energy 125 MeV
Beam current 10 – 100 mA
Normalized emittance en = e/(gb)
1 mm·mrad (77 pC/bunch)0.1 mm·mrad (7.7 pC/bunch)
Energy spread (rms) < 3 10-4
Bunch length (rms) 1 – 3 ps (normal recirculation)~ 100 fs (bunch compression)
• High current mode: 100 mA, 1 mm mrad• Low emittance mode: 10 mA, 0.1 mm mrad• Emittance almost preserved• CSR effects included
Basic parameters
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Compact ERL(1-loop model)
Beam dump
1st TBA arc
Chicane Long straight section
Gun
2nd TBA arc
InjectorMain SC cavities
BeamsExtractor Merger
T. Shiraga, N. Nakamura et al., PAC09
Bunch Compression in cERL
• Bunch compression and decompression successfully simulated.• Optics also optimized for avoiding serious beam loss after decceleration.
Main SC CavitiesDump
Merger
injector
1st arc(R56>0)
2nd arc(R56<0)
Chicane
Extractor
Long straight section
Beams
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
(2)
st =56 fs
(3) (4)
(5)(6)
only b, x,y opt.sx,y opt.
Gun(1)
Initial condition:st =1 psQ=77 pCen=1 mm mrad
time
x-positiony-
posi
tion
Mom
entu
m
5 cm
5 cm6 m
e c
12 ps
Error Effects of Main SC Cavities
• Bunch length and arrival time variations due to RF amplitude and phase errors 0.01 % amplitude and 0.01 deg phase control required for bunch compression• Orbit distortion, emittance growth and bunch lengthening due to alignment error of SC cavities Orbit correction using eigenvector method with constraints(EVC) successfully applied
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Bunch length and arrival time variationsat exit of the 1st arc due to RF amplitude and phase errors in bunch compression
Orbit distortion and emittance growth due to +1-mm horizontal alignment error of 8 main SC cavities in low-emittance mode and their correction
Bunch profile at exit of the 1st arc with ±1-mm vertical alignment error of 8 main SC cavities in bunch compression
DY=0mmst=56 fs
DY=±1mmst=267 fs
DV/V -0.5% +0.5%
DfRF +1.0° -1.0°
1st arc 2nd arc
Optics Design of 2-loop cERL
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Merger
Branch chicane
Adjustment chicane
Extractor
Beam dump
Main superconductor cavitiesDC gun
Layout of 2-loop cERL (tentative)
Optics of 2-loop cERL (tentative)Optics design of 2-loop cERL in progress
M. Shimada et al., ERL09.
cERL Building
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Reconstruction of the East Counter Hall for the compact ERL
Feb. 2009 Jan. 2010
The hall is being cleaned.
Liq. He refrigerator is being installed.
East Counter Hall
Plan View of the Compact ERL (1)
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Liq. He refrigerator systemRF sources
Laser hut
SCC R&D area
Magnetpower supplies
SCC verticaltest area
Compact ERL
Elec
tron
ics
hut
Vacuum hut
Final version of the compact ERL(2-loop, 100mA, 245 MeV)
Plan View of the Compact ERL (2)
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Commissioning will start with a minimum version (1-loop, 10mA, 35 MeV) in FY2012.
Liq. He refrigerator systemRF sources
Laser hut
SCC R&D area
Magnetpower supplies
SCC verticaltest area
Compact ERL
Elec
tron
ics
hut
Vacuum hut
Summary
• Compact ERL (final version : 2 loop, 245 MeV, 100 mA)• Two-loop 5-GeV ERL and 7.5-GeV XFEL-O
ERL Project
R&D in progress• 500-kV DC photocathode gun and injector beamline• Drive laser system for the gun• SC cavities for both injector and main linacs
Compact ERL (cERL)• Design and error analysis of injector and 1-loop cERL studied• Optics of a 2-loop cERL under design• East Counter Hall at KEK renewed as cERL building• Commissioning (35MeV, 10mA, 1 loop) planned in FY2012
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory
Thank you for your attention!
Norio Nakamura, FLS2010, March 1-5, 2010, SLAC National Accelerator Laboratory