1. LASA status for medium-beta cavity Paolo Michelato

2. Talk Overview ESS medium beta SC cavity In kind contribution, prototypes, projects parameters, interfaces etc.. Prototyping activities RF sims & design, HOMs analyses Mechanical design Data and documents management Risk Prototype status: construction, scheduling, cold test Status of series CFTs, procurements … Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 2

3. Medium beta cavities: Technical Performances MB cavity technical requirements Frequency (MHz)704.42 Number of cells6 Geometric beta0.67 Nominal Acc. Gradient (MV/m)16.7 Epeak (MV/m)< 45 RF peak power (kW)1100 Q external5.9 - 8 10 5 Q0 at nominal gradient> 5 10 9 Output energy to 570 MeV 36 SuperConducting 6-cells cavity at beta 0.67 9 cryomodules, 4 cavity each Independent RF power source for each resonators Constraints: – Cavities will be fabricated using INFN design and will be plug compatible with CEA cryomodule boundary conditions. – INFN design is relative only to the cavity itself. – Cavity interfaces, He tank geometry, flanges, tuner connections, etc will be done on the basis of the CEA design. Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 3

4. INFN IN-Kind contribution for Medium Beta INFN In-Kind contribution: Niobium procurement for the fabrication of 36 medium beta cavities. Cavity fabrication of 36 medium beta cavities in the industry, including treatments, tuning, Helium tank integration, etc, accomplishing the ESS requirements in terms of performances, functional interfaces, “plug compatible” with CEA design. Documentation, Certification activities, Ancillaries (flanges, vacuum valves, antennas, frames, etc.) Cold test in a qualified infrastructure. Transportation in special boxes and delivery at the cryomodule assembling facility. Man power for the above activities Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 4

5. Medium Beta prototypes Prototypes plan (not part of INFN in-Kind contribution): Built prototypes of medium beta (MB) and high beta (HB) cavities MB: we are fabricating two MB cavity prototypes with same design but different materials: Large Grain Niobium and Fine Grain Niobium LG and FG are used only for the half cell. All the others components besides HC are done with the same FG material. MB: INFN design, plug compatible with ESS cryomodule Full treatment (BCP, HPR, clean room) done in industry Final handling and test will be done at LASA in the qualified infrastructure. No integration in He tank High beta will be fabricated using LG Nb Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 5

6. Status at May 2016: EM design: done Mechanical design: done Plug compatibility verified (on drawings). Few details to be clarified. FG material (sheets, tubes, etc) for prototypes: available High RRR LG Nb ingot: available LG ingot slicing (wire cutting): done LG disks heat treatment (de hydrogenation, 700°C for 2 hours): done with H 2 monitoring. RRR check on LG material after heat treatment: High RRR recovered. Prototype status (1/2) Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 6

7. Prototype status (2/2) Status at May 2016: Deep drawing tool (3 dies) design and fabrication: done First deep drawing of half cells (HC): done First HC mechanical and EM measurements: under way. Activities for the technological transfer of the cavity processing and handling of the industry under way. BCP, HPR, cavity handling in clean room, integration studies, etc Cavity tuning machine refurbishment: in progress LASA Vertical test adaptation for 700 MHz cavities: under way Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 7

8. The medium beta cavity Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 8

9. Design phylosophy: -Boundaries fully compatible: Beam pipes, couplers, flanges, tank and tunner connection using the same design of CEA prototype. -We design the cells! Our goal: -To have large cell-to-cell coupling factor, k>1.5% -Allowing for a slight modest sacrifice on E peak and R/Q Design Phylosophy Riris = 5 cm, this large Riris gives us a large k, hence large modes seperation (+30%), also a better coupling of HOMs to the outer cells. Cavity shape Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 9

10. ParametersINFN designESS spec. R iris (mm)50≥47 Geometrical beta0.67 Frequency (MHz)704.42 Acc. length (m)0.855 Cell to cell coupling k 1.55% ↗ (+26% ) π-5π/6 mode sep.(MHz) 0.70 ↗ (+30%) >0.45 G (Ω)198.8 Optimum beta, β opt 0.705 Max R/Q at β opt (Ω) 374 ↘ (-6%) E acc at β opt (MV/m)16.7 E peak /E acc 2.55 ↗ (+7%) E peak (MV/m)42.6< 45 B peak /E acc (mT/MV/m) 4.95 ↗ (+3%) Q 0 at nominal gradient>5×10 9 Q ext 7.8×10 5 5.9~8×10 5 INFN-LASA MB cavity design Pi-mode E-field Fundamental modes R/Q Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 10

11. Qext calculation and HOMs Qext calculation, in ESS specification range With CEA power coupler D Qext Sensitivity to Fabrication Errors HOMs, >5 MHz from machine lines F=1742.4 MHz Max R/Q=23Ohm Qext=9.6×10^5 Machine Lines 352.210 704.420 1056.630 1408.840 1761.050 2113.260 2465.470 1029.659 Dipole mode Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 11

12. Model & Materials Cavity parameter INFN Design Cavity wall thickness (mm)4.5 Stiffening ring radius (mm)70 Beam tube diameter (mm)136 Cavity internal volume (l)69 Tank volume (l)45.3 Tank weight (kg)34.4 Cavity weight (kg)78.1 Internal surface (m 2 )1.8 Nb parameters 295K 4K Young’s Modulus(GPa)106125 Yield Strength(MPa)50-70470-660 Density (kg/m 3 )8750 Poisson’s ratio0.4 Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 12

13. Interfaces PDR, LASA, 19 May 2016 Andrea Bignami, INFN LASA.

14. Parameters: Pressure Limit - RT PDR, LASA, 19 May 2016 Andrea Bignami, INFN LASA. Pressure test scenario: -Cavity fully constrained -Pressure in the tank The maximum pressure allowable is -2.60 bar for 50 MPa VM (worst scenario) -3.64 bar for 70 MPa VM (best scenario)

15. ESS quality control: SCHEME: actors Managing System Quality Control INFNIndustry INFN Managing system Database (parameter analysis) INFN Experts Check Cold RF test Q 0 vs. Eacc CEA STRING ASSEMBLY ESS (approval) Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 15

16. ESS quality control: SCHEME NCR Cavity production data Managing System Quality Control INFNIndustry INFN Managing system Database (parameter analysis) INFN Experts Check Cold RF test Q 0 vs. Eacc CEA STRING ASSEMBLY ESS (approval) NCR Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 16

17. ESS quality control: SCHEME NCR Managing System Quality Control INFNIndustry INFN Managing system Database (parameter analysis) INFN Experts Check Cold RF test Q 0 vs. Eacc CEA STRING ASSEMBLY CAVITY with TANK Documents for cold RF test acceptance ESS (approval) NCR Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 17

18. ESS quality control: SCHEME NCR Managing System Quality Control INFNIndustry INFN Managing system Database (parameter analysis) INFN Experts Check Cold RF test Q 0 vs. Eacc CEA STRING ASSEMBLY CAVITY with TANK ESS (approval) Documents for full equipped cavity acceptance (for string assembly) NCR Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 18

19. ESS quality control: SCHEME Managing System Quality Control INFNIndustry INFN Managing system Database (parameter analysis) INFN Experts Check Cold RF test Q 0 vs. Eacc CEA STRING ASSEMBLY MODULE ESS (approval) Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 19

20. Cavity not reaching ESS specs at Vertical Test (Q 0 and/or E acc ) Risk Identification and Analysis Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 20 EventCauseImpactMitigationLikelihoodOwner Cavity not reaching ESS specification after VT: Q 0 too low E acc too low QuenchCavity with reduce performance Scan Nb sheets to avoid defects Provide spares cavities To be address XFEL experience is 2 % on sheets. Worste case scenario few cavities ESS Improper treatments at vendor Cavity with reduce performance Improve QA/QC To be assestINFN

21. Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 Prototypes Fabrication Schedule Mbeta FG delivery: Mid of September Mbeta FG EBW: Mid July 21

22. Prototypes Fabrication Schedule Comments on prototype scheduling Medium Beta FG EBW: mid of July 2016 Chemistry (bulk and final) + tuning: between mid of July and mid of September Cavity delivery at LASA: mid of September Cavity installation on cold insert: 1 - 2 weeks Cold test: 1 week First results: end of September / first week of October It could be integrated in the He tank and tested in the demonstrator at CEA. Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 22

23. Cycle for prototypes and main checks Cavity EBW Pretuning BCP2: 50 - 70  m Annealing De Hydrog. Tuning Final BCP: 20  m Accessories installation Final Check BCP1_1: 20  m Bead Pull in CR 3 x tot: 60  m Optical Insp. Mechanical Check Mechanical check Leak test RF Each step: Frequency, Weight F. Flatness with bead pull in CR Weight RF F. Flatness with bead pull in CR Mechanical check RF Optical Insp. Mechanical check Leak Test RF (spectrum) Outcoming insp. Leak test RGA Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 23

24. Prototype status Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 24

25. Prototype status:deep drawing Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 25

26. Prototype status:deep drawing and RF measurement Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 26

27. Prototype status:deep drawing RF and 3D measurement Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 27

28. LASA infrastructure upgrade Cavities will arrive from EZ ready for the cold test. In any case LASA infrastructure must be in position to handle ESS cavities, to do HPR, to pump and vent using slow pumping / slow venting system,… New cold insert dedicated to ESS cavities will be available Under construction at EZ Delivery foreseen by June Can support naked cavities and cavities integrated in the He tank Main accessories already in house: Cavity vacuum components, LHe transfer line, LHe level sensor, pressure gauges for LHe bath, etc Temperature sensors: buying process in progress Second sound detection system upgrade: in progress Cavity frame: Titanium. Delivered with the cavity. Frame geometry: CEA compatible. HPR new nozzle head, adjustment of HPR mechanics: in progress. Cavity handling tools: design done, waiting for quotation. Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 28

29. Cold insert at LASA Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 29

30. E. Zanon infrastructure upgrade Upgrade of E. Zanon infrastructure for prototypes in progress Infrastructure was tuned for EXFEL and LCLSII cavities. UPGRADES Tools for cavities handling in the infrastructure. Cavity handling in the clean room: cavity weight is about 3 times more! BCP and acid plant cooling power. New pump, new heat exchanger, new flow controller, etc UPW system: adaptation of pressure control system to avoid cavities deformation during pressure test (for leak check) before BCP HPR mechanical and hydraulic adjustment Cleaning and rinsing etc Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 30

31. Series cavities: INFN IN- KIND contribution. SCHEDULING 31 Scheduling and milestones: nothing changed Delivery at CEA of first 4 cavities ready for the installation by the end of 2017. Further cavities delivery rate: 4 cavities/month Last cavities delivery: September 2018

32. Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 32 Series medium beta cavities INFN on the basis of its experience and what has been done so far is ready to start the procurement process for Niobium and Cavities. Cold test for series under definition with DESY. It will be finalized once the schedule is fixed. 2 cavities will be tested in one cooldown. Insert design in progress Contract can be signed CEA Interface document: available in draft form CEA drawings: available Mechanical “plug compatibility” verified “on paper”, few details to be clarified Acceptance criteria (ESS + CEA): to be defined He tank: CEA design, no change foreseen

33. The End Paolo Michelato, ESS PDR, INFN-LASA, 19 May 2016 33