Cavity Work-Package in EDR phase

H. Hayano 01282008 for Lutz Lilje

Cavity Work-Package Definition

• WP-C1: Gradient performance

• WP-C2: Fabrication

• WP-C3: Preparation

• WP-C4: Cavity Design

WP-C1: Gradient performance

1. Tight-loop effort2. Production-like effort3. Preparation for ultimate cavity batch4. Single cell program5. Common performance evaluation6. Gradient proposal for EDR

WP-C1-1: Tight-loop effortFinalize the tight-loop process

• Package should demonstrate repeatability with in each participating lab. Then an inter-laboratory comparison should follow facilitated by cavity exchange. Re-evaluation whether second loop is needed.

• Cavity treatment and testing. Measurement data. Data comparison.

• 2-3 SCRF labs(FNAL, JLab, KEK, DESY), 3 cavities per lab, 3 tests each cavity.

• milestones All cavities tested by mid of 2008. Data comparison by fall 2008. Re-evaluation by fall 2008.

WP-C1-2: Production-like effort1. Treat 30 cavities with EP + ethanol process

• Repeat process (If needed in case of underperformance) at least once. Apply T-map on as many cavities as possible, at least all cavities below 30 MV/m.

• Deliverables: Cavity treatment and testing. Measurement data. • SCRF labs(FNAL, DESY), 30 cavities.• Milestones: All cavities tested by end of 2008.

2. Treat 20-30 cavities with EP + Degrease

• Repeat process….(same above)

• Deliverables: (same above)

• SCRF labs(FNAL, Jlab, KEK, DESY), 20-30 cavities.• Milestones: All cavities tested by end of 2008.

3. Treat 10-20 cavities with EP + fresh EP

• Repeat process …(same above)

• Deliverables: (same above)

• SCRF labs(Jlab, KEK), 10 cavities.

• Milestones: All cavities tested by end of 2009.

WP-C1-3: Preparation for ultimate cavity batch1. Evaluate data from tight-loop and production data

• Overall evaluation of data available by end of 2009.

• Deliverables: Report on data comparison. Recommendation for ILC cavity process.

• Candidate labs(FNAL), by Database and Scientist.• Milestones: Report and recommendation by end of 2009.

2. Treat 30 cavities with ILC process

• Repeat process (If needed in case of underperformance) at least once. Apply T-map on as many cavities as possible, at least all cavities below 30 MV/m.

• Deliverables: Cavity treatment and testing. Measurement data.

• Candidate labs(FNAL, KEK), 30 cavities.• Milestones: All cavities tested by end of 2010.

WP-C1-4: Single cell Program1. To be discussed.

WP-C1-5: Common performance evaluation1. Database setup

• Develop basis for an ILC database. Review existing database. Choose common database system.

• Deliverables: Database for cavity process and testing data. • Candidate labs(FNAL, Jlab, KEK, DESY), by Scientist and IT engineer.• Milestones: Evaluation by end of 2007. Choice of database by spring

2008, Database in place by mid 2008.

2. Data evaluation between laboratory

• Develop schemes for inter-laboratory data evaluation. Evaluation of data sets available. Define data sets requested from labs. Compare data analysis done by participating labs. Evaluate data relevant for ILC project.

• Deliverables: Report on evaluation of existing data sets. Proposal for data sets.

• Candidate labs(FNAL, Jlab, KEK, DESY), by Scientist.• Milestones: Report on evaluation by end of 2007. Proposal for database

by mid 2008.

WP-C1-6: Gradient proposal for the EDR1. Definition of vertical test gradient specification for ILC

• Re-visit Snowmass and S0 specification. Take into account more flexible power distribution. Develop a final specification for vertical test assuming an operational gradient of 31.5MV/m in the machine.

• Deliverables: Report on tolerable gradient spread in ILC (together with Main Linac and LLRF). Final specification.

• by Scientists.• Milestones: Report on tolerable gradient spread by end of 2007. Final

ILC specification for gradient spread in vertical tests by mid 2008.

2. Final proposal for ILC gradient

• Data evaluation of all existing data by end of 2009. Report with proposal for ILC gradient by end of 2009.

• Deliverables: Report.

• by S0 task force.• Milestones: Report by end of 2009.

WP-C2: Fabrication

1. Material2. Alternative materials3. Fabrication method4. HPV regulation

WP-C2-1: Material1. Material specification

• Develop full specification for ILC baseline fine-grain niobium material. Review XFEL specification.

• Deliverables: specification for cavity material.

• by Scientists, engineer of FNAL, Jlab, KEK, DESY.• Milestones: Specification ready by 2011.

WP-C2-2: Alternative Materials1. Large grain cost evaluation

• Review available material on large grain niobium material cost. Investigate cost effective cutting methods.

• Deliverables: Report on cost difference for large-grain material.

• by Scientists, engineer of FNAL, Jlab, KEK, DESY.• Milestones: Report ready by 2008.

2. Large grain multi-cell cavity development and testing

• Built and test several multi-cell cavities. Repeat process (If needed in case of underperformance) at least once. Apply T-map on as many cavities as possible, at least all cavities below 30 MV/m. Comparison of different surface treatments on multi-cell cavities.

• Deliverables: Cavity treatment and testing. Measurement data. Report of data comparison with baseline material. Material specification.

• Candidate labs(Jlab, DESY), 10-20 cavities. ~2 tests each cavity.• Milestones: All cavities tested by mid of 2010. Data comparison by fall

2010. Final report by end 2010.

WP-C2-3: Fabrication method1. Analysis of EBW performance

• Evaluate available data on performance of EB welds by both established and new cavity vendors. Include laboratory in-house fabrications where appropriate. Implementation of sufficient diagnostic capability in participating labs (e.g. temperature mapping). Development of cavity autopsy for the weld region on defective cavities (destructive or non-destructive).

• Deliverables: Report on performance of EB welds. T-mapping for diagnostics. Method of defect detection in weld region.

• by Scientists, engineer, and SCRF labs.• Milestones: Report until mid 2008. T-mapping diagnostics by mid 2008.

Method by 2009.

2. EBW specification

• Review XFEL specification for EBW. Develop additional qulity control for EBW at companies. Write specification.

• Deliverables: Specification.

• by scientists.• Milestones: specification by end of 2008.

WP-C2-4: HPV regulation1. HPV regulation

• Develop common understanding of requirements to fulfil high-pressure vessel code regulations especially for how to deal with niobium material.

• Deliverables:

• by .• Milestones:

WP-C3: Preparation

1. Baseline process

2. Alternatives

WP-C3-1: Baseline process1. Process specification

• Develop full specification for ILC surface process. Review XFEL cavity surface process.

• Deliverables: specification for cavity process. EP, HPR, assembly and QA thereof.

• by Scientists engineer at FNAL, Jlab, KEK, DESY.• Milestones: Specification ready by 2011.

2. Surface Analysis in support of baseline process

• Review ongoing R&D activities on niobium RF surfaces. Develop program to improve QC for ILC surface process.

• Deliverables: Development of an R&D program. Managing program with supporting institutes.

• by Scientists engineer at Jlab, Cornell.• Milestones: Program ready by mid 2008.

WP-C3-2: Alternatives1. Tumbling

• Evaluate whether tumbling as an additional intermediate process step for a cavity is necessary to achieve more homogeneous performance.

• Deliverables: Comparative study on cavities with and without tumbling (possibly on single cells).

• by Scientists of KEK, by single cell program.• Milestones: Report by end of 2008.

2. Dry-Ice

• Evaluate whether dry-ice cleaning as an additional intermediate process step for a cavity with main coupler is feasible. Demonstrate proof-of-principle.

• Deliverables: Report on feasibility. Proof-of-principle.

• by Scientists.• Milestones: Report by end of 2008.

WP-C4: Cavity Design

1. Specification of outer envelope2. Preparation for the cavity shape decision3. Lorentz detuning concept4. Beam dynamics

WP-C4-1: Specification of outer envelope1. Outer diameter, length

• Evaluation of existing designs. Technical comparisons of the designs. Define the outer boundary of the cavity.

• Deliverables: specification.

• by Engineer.• Milestones: Complete specification by Sendai meeting.

2. Sealing technology

• Review existing seal designs. Make technical comparison. Make recommendation for common interface. Finalise specification.

• Deliverables: Review report. Recommendation. Specification.

• by Engineer.• Milestones: Complete review report by Sendai meeting.

3. Input port diameter

• Review existing port design and high power couplers. Make technical comparison (needs definition of criteria). Make recommendation for common coupler port. Finalise specification.

• Deliverables: Review report. Recommendation. Specification.

• by Engineer.• Milestones: Complete review report by Sendai meeting.

WP-C4-2: Preparation of the cavity shape decision

1. Definition of tests

• Review existing cavity design. Define required testing based on Cavity KOM discussion. Develop a detailed schedule to prove a cavity shape can be used in ILC.

• Deliverables: Review report, report on required testing, Schedule.

• by Scientists, engineer.• Milestones: Review report by end of 2007. Report on required testing by

2007. Detailed schedule by mid 2008.

2. Testing of cavity shape alternatives

• Design ILC-compatible alternative shape cavity. Build and test compatible cavities with alternative shapes. Preparation and surface preparation of a number of cavities required by WP above. Repeat vertical tests (if needed in case of underperformance) at least once. Apply T-map on as many cavities as possible, at least all cavities below 30 MV/m.

• Deliverables: Design of an ILC compatible alternative shape cavity. Cavity treatment and testing. Measurement data.

• One SCRF lab (Jlab, KEK, Cornell) per cavity shape, .• Milestones: Alternative design by beginning of 2008. Additional

milestones according to what has been defined.

WP-C4-3: Lorentz detuning concept1. Evaluation of tests

• Review existing Lorentz-force compensation concepts. Comparison of technical concepts including the relevant tuner design. Proposal for a common concept.

• Deliverables: Review report. Proposal for a common concept.

• by Scientists, engineer.• Milestones: Review report by end of 2007. Proposal by mid 2008.

WP-C4-4: Beam dynamics

1. HOM concept

2. Wake fields

3. Alignment

4. Straightness

DESY activity status1. S0 cavity treatment5-th product batch : 15 ZANON, 15 ACCEL -> EP training of HENKEL and

ACCEL.Helium tank welding before vertical test (XFEL scenario). Final process will be

compared for Short etch and EP+ethanol rinse.3 batch; 10 cavities = Short etch, 10 cavities = EP + ethanol, 10 decide later.30 cavities testing by mid 2008. Two cavity vendors comparison.

AC71,AC74,AC80 are put into tight-loop.

2. Cavity package alternatives8 new large-grain cavities are available in late 2008, will be tested by end of

2008.11 large-grain cavities( 8 new + 3 existing) will receive final process of

EP+ethanol rinse.

DESY activity status (cont.)3. S1 module tests

A series of modules will be assembled and/or tested:1. M3* (TTF 2 type cryostat) in early 2008: Test to conform with pressure vessel code (possibly destructive)2. M8 (TTF 3 +) in spring 2008: ( plan was changed to go Saclay first, back to DESY later) Normal module test including piezo tuners, Transport, Second test to check performance3. M3** After repair with a gradient goal of at least 25 MV/m as spare for FLASH. Piezo tuners added4. M10 (XFEL Prototype) assembly autumn 2008, gradient goal >25 MV/m

At least the M8 string could deliver ILC-like performance. The test will be made by mid 2008, so that additional input for S1 would be available.

Independent of the module performance tests, both the transport test for M8, and the test for the pressure vessel code with M3* are of major importance for the ILC.

US activity status1. S0 cavity treatment

Jlab: 30 cycle of EP/VT per year. AC6(38MV/m),AC7(32MV/m): 4 cycles as S0. AC8 started as S0.

KEK Ichiro#5(30-20MV/m) started as S0. AES001,002,003,004 evaluation(16-32MV/m).

Cornell: 1 cycle per month. AC8(28MV/m),AC9(25MV/m) are under qualified. 9-cell re-entrant work. AES new EBW qualification with five 1 cell (4:25MV/m, 1:17MV/m).

New cavity plan: AC10-17(8 cavities), AES005-010(6 cavities) delivery end of 2007.

AES011-016(6 cavities) are ordered.

2. S1 module tests

First cryomodule is ready for test. Next cryomodule …?…

3. Infra-structure

ANL-EP commissioned with 1 cell. FNAL HPR under construction.

CAF-ICB (cryomodule assembly facility at ICB) : two assembly fixtures.

FNAL VT commissioned with AES001 cavity.

AES new EBW is qualified.

New cavity vender : PAVAC (Canada) is under qualifying.