Transcript MICE RFCC Module and 201 MHz Cavity Update

MICE RF Cavities and
RFCC Module Update
MICE RF Workshop
Daresbury Laboratory, UK
April 17, 2012
Derun Li
Lawrence Berkeley National Laboratory
MICE Cooling Channel
Two RFCC modules, four 201-MHz cavities per module, four ports per cavity:
two of them for RF couplers, one for vacuum pump and one for RF probe;
Two beryllium windows per cavity.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
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Page
RFCC Module
Six tuner arms & actuators per cavity, and cavity is supported by strut system.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 33
Page
Current Status of RFCC Module
• RF Cavities and single cavity vessel:
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•
•
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•
All 11 beryllium windows received at LBNL (1st RFCC module)
Ten ceramic RF windows received
Six tuner flexures are being fabricated at Fermilab
Components for 6 actuators are being fabricated
RF coupler design has been modified to eliminate the gap between
the outer coax and the RF loop
• Fabrication of fixturing for the electropolishing is nearly complete
• Mechanical smoothing of the cavity inside surface before EP
• Single cavity vacuum vessel, fabricated at Keller Technology in
Buffalo New York, is complete and is at Fermilab now.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 44
Page
Beryllium Windows
• Eleven beryllium windows have
been fabricated so far:
• Curved thin (0.38-mm thick)
window with TiN-coating on both
sides
• Received two new beryllium
windows recently, these two
windows have been fabricated by
Materion Electrofusion (fomer
Brush-Wellman) to replace the
windows rejected due to excess
distortion with improved brazing
design/technique: no distortion is
observed.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 55
Page
RF Cavity Frequency Tuner Components
• Dual – action
actuator
• Flexure
tuner arm
• RF cavity
Cross-section view
Tuning range:
230 kHz
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 66
Page
Cavity Frequency Tuner Flexure
Finished tuner arm
Jan. 25-26, 2012 in Fermilab
Six full size tuner flexures are being fabricated at Fermilab
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 77
Page
Actuator Component Fabrication
• Component for six actuators are currently being fabricated by a local vendor
• The actuators will be assembled at LBNL
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 88
Page
RF power (loop) coupler
• RF power (loop) coupler design has been modified to eliminate the gap
between the loop and the outer coax tube
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 99
Page
RF Power (loop) Coupler (old)
Cross-section view
MTA RF coupler
Old MICE design
• Testing/experience of the prototype cavity at MTA: sparking at the coupler
• The coupler design has been changed slightly to increase the gap spacing
• The sparking region can be TiN coated if necessary (plan to be tested at MTA
using the prototype cavity)
• Adding diagnostics: arc detector at the coupler region.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 10
Page
10
RF power (loop) coupler
Cross-section view
Cross-section view
• Modified MICE RF power coupler
design is complete, drawing
package has been delivered to
FNAL, and ready for fabrication
• Fabrication of the couplers should
start soon
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 11
Page
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Cavity Measurements
Cavity physical measurement
Cavity frequency measurement
• Physical measurements for the six remaining cavities expected to take
approximately 1-1/2 weeks (60 hours)
• RF measurements and tuning to a center frequency after the EP of all ten
cavities (two spares) at LBNL.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 12
Page
12
Cavity Electropolish at LBNL
Cavity section view
EP rotation fixture at LBNL
• The inner surface of each cavity will be mechanically smoothed and then electropolished at LBNL
using the similar techniques developed at JLab for the prototype cavity
• Fabrication of EP fixturing is complete and electropolishing will start in soon after ES & H approval
• Electropolishing process will take approximately 1- 2 days for each cavity or 4 weeks to complete
all 10 cavities
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 13
Page
13
Cavity Electropolish at LBNL (cont’d)
Cavity section view
New fixture for EP exhaust fabricated,
testing and meeting with ES&H
personnel scheduled.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 14
Page
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Ongoing Simulations of MICE RF Cavity
Study of external magnetic field on MICE RF cavity and coupler (Dr. Tianhuan Luo)
• 3D simulations (from CAD model) using SLAC’s Omega-3P code: f = 201.866 MHz
• MP simulations, and RF breakdown studies with an external magnetic field
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 15
Page
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Single Cavity Vacuum Vessel
Vacuum vessel stand
Vacuum vessel
Vacuum vessel cover plate
Single Cavity Vacuum Vessel and
MuCool Coupling Coil Magnet
Fabrication of the single cavity vacuum vessel is
complete at Keller Technology in Buffalo New York
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 16
Page
16
RFCC Future Work
• RFCC Vacuum Vessel:
• Vessel design is complete but needs to be updated to
incorporate changes to the interface with the new coupling
coil cryostat design
• Fixturing for the assembly process needs to be finalized and
drawings for fabrication generated
• RFCC Module:
• Finalize fixturing for module assembly and shipping
• for aligning the frequency tuners onto cavities
• for inserting the cavities into vacuum vessel
• shipping skid/tilt fixturing for shipping RFCC to RAL
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 17
Page
17
RFCC Future Work (cont’d)
• RF control/analysis: this workshop
• Diagnostics/control/analysis/interfaces
• LLRF control (amplitude/phase) and correlations with
detectors
• Timing signal from detector, and calibration & synchronization
with RF
• DL group should take the leadership and ownership
• LBNL group will assist under MAP support
• Understanding the engineering approach and scope of work
• Development of future plan and define responsibilities of each
group.
MICE
RFCC Module
ReviewDaresbury
at RAL, UK Lab, UK
MICE RFCC
Module
Update –– MICE
MICESchedule
RF Workshop,
Derun
- LawrenceBerkeley
Berkeley National
– May
24,17,
20112012
Derun
Li -LiLawrence
NationalLab
Lab
– April
Page 18
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