Download - 1.3 GHz SRF Cavity R&D Plan
1.3 GHz SRF Cavity R&D Plan
Jiyuan Zhai
ILC Group, IHEP
3rd IHEP-KEK 1.3 GHz SRF Meeting, 7 Dec 2010, Beijing
Outline
• 2011 Plan
– IHEP-01 (LG LL 9-cell w/o HOM) 2nd VT
– IHEP-02 (LG LL 9-cell w/ HOM) fab, VT and dressing
– IHEP-03 (FG TESLA 9-cell w/ HOM) fab and VT
• 2012 and after
– IHEP-02 horizontal test
– ERL (7-cell and 2-cell), 2011-2015
– ADS (beta 0.8, 1.3 GHz 9-cell cavity) , 2012-2015
CW, High Current
IHEP-01 large grain 9-cell cavity
• Fabrication: 2009.2 – 2010.4
• Processing: 2010.4 -5
• 1st VT: 2010.6-7– vacuum 2~5E-7 Pa
– T-mapping, no X-ray mapping
– Kyoto camera inspection
– replica
• 20 MV/m (cell #9, #2 quench)– defects not exactly identified
• Field emission– CP stains or iris defects 0 5 10 15 20 25108
109
1010
1011
Qo Pi mode [4 K] Qo Pi mode initial [1.76 - 1.73 K] Qo Pi mode final [1.88 - 2.02 K]
Eacc, max = 8.4 MV / m
Qo = 3.95 * 108
Po = 164 W
CBP (190 μm), BCP (110 μm), Annealing (750oC, 3 h), Pretuning (94 %), Ultrasonic
(Micro-90 2%, 50oC, 3 h), BCP (20 μm), Ultrasonic (UPW), Low Pressure Rinsing @ IHEP
Ultrasonic (Liquinox 2%, 43oC, 3 h), HPR (8.5 h), Baking (105oC, 48 h), VT @ KEK
Final: Quench (self pulse) / F.E.Eacc, max = 19.8 MV / m
Qt = 1.40 * 1012
Qo = 1.57 * 109
Po = 230 WHe pres. = 2.69 kPaHe temp. = 1.94 K
Initial: F.E.Eacc, max = 6.3 MV / m
Qt = 1.46 * 1012
Qo = 1.66 * 109
Po= 21.9 WHe pres. = 1.36 kPaHe temp. = 1.73 K
1st Vertical Test, July 1, 2010
IHEP-01 Large Grain Low Loss 9-cell Cavity (without HOM couplers)
Q0
Eacc
[MV/m]
IHEP-01 defects and reprocessing
Quench defects
• X-ray photo (cell #9 slot)
• Local grinding (cell #9)
• CBP
Field emitters
• CP stains – 2nd CP attention
• Iris defects – no way to remove, maybe not matter
#2, 340°33 MV/m
#4, 156°> 25 MV/m
#9, 270°, 20 MV / m1
mm
#3, 85°> 21 MV/m
equator
1 m
m
IHEP-01 2nd processing and VT schedule
Task [preparation] Time (days) Notes
Local grind [new inspect tool, X-ray photo] Dec.12-17 (5) Totally 30 days
CBP (100 μm) [jig, stone, maintain] Dec. 20-28 (7) Visa document
LPR, ultrasonic Dec. 29-30 (2)
1st CP (100 μm) and outside CP [acid] Jan. 7 (1)
HPR (1 hour) [jig?, test, avoid damage!] Jan. 7-8 (2) Then 10 spare days
Annealing (Ningxia or Beijing) Jan. 17 -21 (5)
Pretuning (vertical) , jig modify & fitting Jan. 24-28 (5) Holiday 1.29 – 2.9
2nd CP (10 μm) Feb. 10 (1) Avoid stains!
HPR (4 hours) , dry and pack [UPW] Feb. 10-13 (3)
ship to KEK Feb. 14-21 (7)
HPR (8 hours), assemble, baking, T-mapping Feb. 22-28 (7) TTC 2.28 - 3.3
VT, Inspection, back to IHEP Mar. 1-11 (8) Before TTC?
IHEP-02 large grain cavity with HOM
• low loss shape
• end cell w/o HOM optimization
• TESLA HOM coupler
• quasi-TESLA end plate
• tuner and bellow in the middle
• Ti helium vessel
• magnetic shield tubes inside
• magnetic shield end caps outside
• plug-compatibility
• install into IHEP short cryomodule
• distance from input coupler to end cell longer ( > 54 mm)
• total length longer
IHEP-02 End Group
• IHEP-02 will be tested in FNAL or JLAB in 2011 for several times
• try to adopt TELSA flanges and end plate to avoid new tooling, transitions and fixtures, except the input coupler port flange
IHEP-02 Plan
Task Time Notes
Half cells and Dumbbells fabrication Aug – Nov 2010 Zhao’s talk
Dumbbell reshaping and trimming Dec 2010 no iris intensive grind
End Group and Cavity EBW Dec 2010- Mar 2011 visa document
Processing (CBP+CP+HPR) April - May new interfaces in IHEP
Ship to FNAL or JLAB mid June Interfaces preparation
1st VT June
CP or EP and VT (25 MV/m) July - August SRF11: July 24-28
Helium Vessel, bellow, tuner flange Sept CP after jacket welding?
Assemble and install tuner Oct 2011clean room qualityinput coupler cold part
2 K pipe weld, cryomodule install End of 2011
IHEP-02 Interfaces (FNAL)• only 1 of the 6 cavity flanges is different from TESLA
– RF input through input coupler port, fixed coupling (what Qext?)
• order input coupler flange and antenna from Kyocera
• order helicoflex (CS20M45CI15037) from Usui
– make new EP sealing for input coupler port
– bottom flange evacuation (explosive and vacuum valve)
– no electron monitor (top flange blanked)
– HOM coupler pickups blanked
• limited number of thermal sensors– second sound transducers can’t replace T-mapping system
• no CP facility for the 1.3 GHz 9-cell cavity, CBP available
• make same FNAL/ANL jig for EP, HPR, CBP…
• pretuning only vertically (can’t use auto-machine due to shape)– bring manually tuning jig (mid and end) and software
• fixed when Shekhar Mishra visit IHEP (Feb 2011)
IHEP-02 Interfaces (JLAB)
• VT same with FNAL
• EP: cavity length, sealing, slight difference in the beam tube diameter, EP cathode rod available
• CP available
• Kyoto camera and QM1
• limited T-mapping
• horizontal pre-tuning OK
• reduced new interfaces as MHI-08
• sapphire HOM antenna for horizontal test
• order antennas from Kyocera
• Bob Rimmer IHEP visit (Feb 2011)
IHEP-03 fine grain TESLA cavity plan
Task Time Notes
Dies and fixtures Jan - Feb 2011
Half cells and Dumbbells fabrication Mar - June 621 EBW machine?
End Group and Cavity EBW April - July
Processing or not August - September no CBP, no CP
Ship to FNAL or JLAB mid October
Processing and VT (25 MV/m) October - November interfaces no problem
Helium Vessel, bellow, tuner flange? End of 2011
IHEP-03 can be a backup for IHEP-02 module test, except the input coupler port.
Or install to STF phase 2 CM2?
II: BXERL
Beijing Light Source (2016-2025)
Main RingE=5 GeVC=1200m~ 1 nm
BoosterC=300m
250MeVLinac
Return
Gun
5 GeV SRF Linac 1.3 GHz 7-cell Cavities
1100m
650m
I: Low Emittance SR
Beijing Science Park
50 km North of downtown Beijing, include New SRF Lab
ERL test facility cavities
• Similar to KEK cERL
• 35 MeV, 10 mA, 1.3 GHz RF
• Photocathode DC gun and two 2-cell cavities as injector
• Two 7-cell cavities of the main linac
• 2010-2011: design (CDR-0 finished)
• 2012-2013: fabrication and test (6 cavities)
• 2014-2015: dressing, horizontal and beam test
• Input couplers and HOM absorbers are challenging
1515
X区
ERL Test Facility in Hall #1 at IHEP campus
50 m x 12 m = 600 m2
Preliminary cost estimation : ~ 22 M USD
China ADS
IS
SC RFQ
2016CIADS (1.7 B CNY)Reactor : ~10 MWAccelerator:50 MeV / 10 mA120 MeV ?
2022ADS PrototypeReactor : ~100 MWAcce : 600~1000 MeV / 10 mA
2032ADS DemoReactor : ~1000 MWAccel : 1.5 GeV/ > 10 mA
Possible site: Ordos, Inner Mongolia
OrdosOrdos
Jin PingJin Ping1800 km1800 km1800 km1800 km
Dayabay I & II CSNS upgrade
BEPCII and BESIII
ADS and China’s Future Neutrino Physics Experiment
ADS
CJPL
2400 m deep2400 m deep
High energy end for the ADS linac
1.3 GHz 9-cell cavity (beta=0.8) SRF accelerator unit (2012-2015)
Linac configuration under discussion
SRF facilities for cavity development
• Vertical test
• Ultrapure water, High pressure rinsing system, clean room
(to be qualified)
• VT Dewar and helium recycling
• New cryogenics system
• T-mapping
• EP for high Q and high gradient
• New SRF lab, EBW machine, press and vertical trimming machine…
Summary
1. IHEP-01 9-cell cavity made the first try on the technique and infrastructures needed for the multi-cell cavity development.
2. IHEP-02 or IHEP-03 will demonstrate the 1.3 GHz SRF integration in IHEP, providing experience for ERL and ADS R&D in China.
3. ILC 1.3 GHz SRF technology will extend to various large scale projects in China - electron or proton, pulsed or CW machines.
4. Infrastructures and industrial partners of certain scale and qualification will soon be the limit for this development.
2006-2010
2011-2015
2020 -2030