1. SPX0 Cavity and Cryomodule Systems WBS 01.02.01.03.05 Genfa Wu SRF Scientist ASD/RF SPX0 Review 23-24 August 2012 SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012 For the JLAB/ANL/SLAC Collaboration Team

2. Outline  WBS Scope of this system  Requirements  Design  Interfaces  Risks considered (Fault Analysis)  Summary 2 SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012

3. Cavity and Cryomodule System Scope 3  Fabricate and test major cavity system components.  Fabricate, test and install a single cryomodule containing two SRF deflecting cavities (MARK II) with LOM/HOM waveguide dampers and tuners in Sector 5 of the APS storage ring. SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012

4. Cavity and Cryomodule System Requirements  Discuss requirements, PRD, ESD as exist.  What KPP’s are supported (if applicable)  Discuss the technical goals / science (if appropriate) 4 SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012

5. SPX0 Physics  To demonstrate operation of two fully-powered independently-controlled superconducting deflecting cavities with beam, including quantitative measurements of their impact on the beam. This test will require low-level rf control, high-power rf, interlock systems, timing and synchronization systems, cavity alignment, beam diagnostics, controls, and beam feedback.  To demonstrate synchronization of a beamline laser with the deflecting cavities at the sub-ps level. When operated in phase, the two cavities will increase vertical beam size everywhere around the ring, and therefore in this configuration will not be compatible with normal user operation. The tests will only be conducted during storage ring beam study periods. When operated in opposite phases with zero net deflecting voltage, no significant effect on the beam is expected, so that the cavities could be operated and tested during user operations. However, this mode of operation will need to be confirmed as acceptable for the user operations first. 5 SPX0 Physics Requirement Document SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012

6. SPX0 Main Parameters QuantityValue Electron beam current100 mA Number of cavities2 Total voltage1.0 MV RF Frequency2815.486 MHz Cavity tunability200 kHz Source tunability1.5 kHz Operating temperature2 K Longitudinal non-deflecting mode impedance <0.44 M  -GHz Horizontal non-deflecting mode impedance <1.3 M  /m Vertical non-deflecting mode impedance <3.9 M  /m 6 SPX0 Physics Requirement Document SPX0 Cryomodule Engineering Specification Document SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012

7. Cryomodule Engineering Specification* (1)  Cavity nominal operating deflecting voltage 0.5 MV with Q0 ≥ 1e9  Cavity Qext = 1e6, RF source 5 kW  Cavity Tuner: 2815.486 MHz ±200kHz, resolution < 40Hz  Cavity alignment: –  X : ±0.5 mm,  Y : ±0.5 mm,  Z : ±1.0 mm  Cryomodule alignment: –  X : ±0.5 mm,  Y : ±0.2 mm,  Z : ±1.0 mm  Cryogenic total heatload goal –2 K heatload < 50 W (+/-5 W) –80 K heatload < 260 W  Profile needs to fit APS tunnel (Sector 5 envelop) –73.4” flange to flange –Maximum height from beam line < 40” –Floor to beam < 52.52” Advanced Photon Source Upgrade (APS-U) project 7 *See Engineering Parameters Table for complete details

8. Cryomodule Engineering Specification* (2)  Bellows –Inter-cavity rigid connection –Warm to cold transition bellows Unshielded Longitudinal movement ±0.5 mm, transverse movement ±1.0 mm  Magnetic shielding: ≤ 5 mili-Gauss  Dampers –External LOM load (2 kW) –Internal HOM load ( 500 W, water cooled)  Windows –LOM broad band, 5 kW average power –FPC broad band, 5 kW - 20 kW average power  Interfaces: water, vacuum, RF, instrumentation. *See Engineering Parameters Table for complete details Advanced Photon Source Upgrade (APS-U) project 8

9. Deflecting Cavities SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 9 HOM Damper LOM Damper HOM Damper CCA3 design CCA3 fabrication Input Coupler Specification

10. Deflecting Cavity Performance SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 10 CCB1 is fully satisfied to the spec CCA2 achieved gradient requirement

11. SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 11 Stability Threshold Monopole Impedance Monopole Stability Threshold Horizontal dipole Vertical dipole Dipole Stability Threshold Vertical Dipole Impedance Stability Threshold Horizontal Dipole Impedance Total HOM/LOM power for Mark-II: <0.5/1.8kW for APS 200mA, 24 beam bunch mode Impedance Calculations for Single Cavity

12. SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 12 Impedance Calculations for Multiple Cavities The propagating modes up to 5 GHz are also damped to meet the desire requirements. There is no trapped mode between the cavities. Liling Xiao et al., Higher Order Modes Damping Analysis for the SPX Deflecting Cavity Cryomodule, IPAC 2012

13. SPX0 Helium Vessel Design SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 13 Helium Return Helium Supply Tuner Attachment Points Nitronic Rod Mount

14. Stress Analysis of a Dressed Cavity SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 14  With the small bellows design, the peak stress in warm CC-A3 cavity dropped to 6,100 psi, which is below the allowable of 6,310 psi. (Conservative to design to peak stress.)

15. SPX0 Tuner Design SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 15 SPX Tuner Design Specifications Tuning Range +/- 200 kHz Tuning Resolution 40 Hz Rapid Detuning 3 kHz < 1msec

16. SPX0 Tuner Design Status: Cavity Measurements  SPX Cavity (CCA3-1) Exercised in Modified C100 Tuner Test Stand –Cavity instrumented with 4 strain gages –Axial Force, Length, and Frequency measured as cavity stretched SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 16

17. SPX Tuner Design Status: Cavity Measurements SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 17 Tuning Sensitivity (Mhz/mm)* Cavity Stiffness (klbs / in)** Predicted 12.2113.5 Measured 13.0101.6 * - The tuning sensitivity with a He vessel is expected to decrease by 26% ** - The stiffness with a He vessel is expected to increase by 12% Modeling Validated

18. Horizontal Test Stand 18 Advanced Photon Source Upgrade (APS-U) project Horizontal cavity test  5 kW amplifier  50 W Cooling @2K  Analog and Digital RF Horizontal test of a dressed cavity is scheduled in October 2012

19. ATLAS test area Advanced Photon Source Upgrade (APS-U) project SPX Review, March 3-4 2011 19 Advanced Photon Source Upgrade (APS-U) project

20. Cavity Layout for SPX0 Alignment Advanced Photon Source Upgrade (APS-U) project 20 One room temperature shielded beam line bellows each side (not shown)

21. Bellows adjustment and beam steering ranges Advanced Photon Source Upgrade (APS-U) project 21  Transition bellows allows +/- 0.5mm  Beam line bellows allows +/- 1.0 mm  Beam steering during beam studies allows +/- 0.66mm If a cavity misses beam line by 0.5 mm, adjusting cryomodule alone can bring cavities back to perfect alignment of electric centers. Adjustment bounding boxes

22. Alignment Progression Advanced Photon Source Upgrade (APS-U) project 22 1.Wire stretch on CMM allows relation of alignment balls to electrical center line of cavity 2.Comparison to pre-HV measurements provide reference 3.Create custom spool piece to link cavities and Use fiducials + wire stretch to confirm that pair electrical center matches combination of pair centers 4.Use alignment balls to transfer fiducialization from beam line to space from on rabbit ears 30 um error each time fiducialization transferred Courtesy of Josh Feingold 1 2 3 4

23. JLAB Stretched Wire Measurement Advanced Photon Source Upgrade (APS-U) project 23 Slide from Josh Feingold

24. Low Impedance Unshielded Bellows Advanced Photon Source Upgrade (APS-U) project 24 Bellows Bunch length [mm] Nominal loss factor K loss [mV/pC] Shielding APS364Yes SOLEIL320Yes SPEAR3367Yes NSLS-II318Yes American BOA IV 3455No American BOA IV 101.517No Loss Factor: 1.517 V/nC Prototype bellows are being fabricated Materials: Copper plated Stainless Steel or Phosphor copper alloy

25. SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012 25 CLEAN ROOM CAVITY STRING

26. SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012 26 COLD MASS

27. SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012 27 COLD MASS

28. SPX0 Review of the Advanced Photon Source Upgrade Project 23-24 August 2012 28 CRYOMODULE ASSEMBLY

29. SPX0 Cryogenic Design  SPX0 will use existing CEBAF prototype end cans –No 5K circuit 5K heat load will be sunk to 2K with heat straps added to stabilize thermal loads as required (waveguides, beamtubes) –Heat exchanger will be external to cryostat  SPX0 will run with liquid dewars and vacuum pumping –Goal - 2 K heat load for the cryostat is 50 watts –The vacuum pump planned for SPX0 has been measured at 64 watts at 23 torr (2.0 K) –If more pumping is needed there is an option to add additional pumping  Helium riser heat flux limit estimated by Gary Cheng –98 watts at 2.0K, 59 watts at 2.07K  Thermal shield will use LN2 for SPX0 –Will test at JLAB with ~50K helium  Heat load estimates do not include male bayonets and distribution system SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 29

30. Cryomodule Heat Load SPX0 Heat Load components2 kShield per Heat loads per Item#StaticDynamicTotal StaticDynamicTotal Cavity2 714 0 HOM411.32.39.20.370.721.094.36 LOM21.360.211.573.1412.050.3512.424.8 FPC21.140.481.623.245.090.455.5411.08 Beam Tubes20.140.160.30.6 Component Totals9.2820.9030.1835.84.540.24 Static Cryostat Estimate12 144 Total 42.18 184.2 SPX0 Review of the Advanced Photon Source Upgrade Project, 23-24 August 2012 30 LOM FPC HOM Beam pipe

31. Interfaces 31 Director's CD-2 Review of the Advanced Photon Source Upgrade Project 11-13 September 2012 Cryogenic P&I D

32. Interfaces 32 Director's CD-2 Review of the Advanced Photon Source Upgrade Project 11-13 September 2012 Cavity P&I D HOM as an example:

33. Cavity and Cryomodule Fault Analysis Summary (1)  Accidental venting of beam line, insulating vacuum  Cryogenic trip or power outage  Helium circuit leak to insulating vacuum  Helium circuit leak to beamline vacuum  Cavity quench  Window arcing  Tuner failure  Beam line valve failure  Cavity performance degradation  Excessive heating to 2K circuit  Beam line mis-alignment greater than spec 33 Director's CD-2 Review of the Advanced Photon Source Upgrade Project 11-13 September 2012

34. Cavity and Cryomodule Fault Analysis Summary (2)  Cavity mis-alignment  HOM load bonding failure  HOM load SiC performance degradation  HOM load water flow stops  HOM load water leak in insulating vacuum space  Excessive microphonics  Field probe faults  Cryogenic acoustic resonance 34 Director's CD-2 Review of the Advanced Photon Source Upgrade Project 11-13 September 2012

35. Summary 35 SPX0 Design solutions have been developed Cavity prototypes qualified Prototypes of critical components are in progress Vertical alignment is critical Low impedance bellows need beam test LOM/HOM damping must be very strong Cryomodule design mostly completed, ready for procurement/fabrication Director's CD-2 Review of the Advanced Photon Source Upgrade Project 11-13 September 2012