1. TTC Meeting Frascati Dec 5-7 Bernd Petersen WG3: Module Test-Stand Summary Charge of the working group: Define scope of module test-stand activities with and without beam Conveners: Hitoshi Hayano, Shekhar Mishra, Bernd Petersen,

2. TTC Meeting Frascati Dec 5-7 Bernd Petersen We had 6 talks: Test program on the CMTB/CMTF at DESY (Yury Bozhko, DESY) (test without beam) Status and plans for the ILC-module design (Tom Peterson,FNAL) (object which needs tests) HOM measurements at the TTF (Marc Ross, SLAC)) (very important tests with beam) Beam measurements at TTF (Hans Weise,DESY) (another examples for very important tests with beam) Status of ILCTA at FNAL (Sergei Nagaitsev, FNAL)) (plans for tests with and without beam) Planned beam measurements at STF (Hitoshi Hayano, KEK) (test with beam in two phases)

3. TTC Meeting Frascati Dec 5-7 Bernd Petersen In this summary I will concentrate on the test stand issues (several other detailed aspects were discussed by the experts)

4. TTC Meeting Frascati Dec 5-7 Bernd Petersen Status and plans for the ILC cryomodule design Tom Peterson, Fermilab TESLA Technology Collaboration Meeting Frascati, 6 December 2005

5. TTC Meeting Frascati Dec 5-7 Bernd Petersen TTF cryomodule is our reference

6. TTC Meeting Frascati Dec 5-7 Bernd Petersen Type IV cryomodule will differ from type III+ in the following general areas Cavity iris-to-iris spacing reduced to 283 mm –Reduces length from 12.20 to about 11.8 m, get ~0.75 packing Slow tuner modified to allow closer cavity-to-cavity spacing (could mean switching to blade tuner design, but choice still open) Fast tuner -- new design Quad/corrector/BPM package under center post, hung from 300 mm tube, not on rollers (diverging from X-FEL) –Two major module types, one with quad and one without

7. TTC Meeting Frascati Dec 5-7 Bernd Petersen More differences of Type IV cryomodule from type III+ Interconnect features modified to accommodate input coupler at end of cryostat Quad current leads may be new and different, with local impact on thermal shields and vacuum vessel ports Provisions for quad power lead connection at center of module Some pipe sizes will be increased for lower pressure drops with high flow rates -- would like to retain long cryogenic unit lengths up to limit of 300 mm pipe and cryo plants. Present effort includes re-analysis of heat loads, flow rates, and cryogenic system thermal process.

8. TTC Meeting Frascati Dec 5-7 Bernd Petersen (Increase diameter beyond X-FEL) (Increase diameter beyond X-FEL) (Review 2-phase pipe size and effect of slope)

9. TTC Meeting Frascati Dec 5-7 Bernd Petersen Some critical open design issues Quad/corrector/BPM package is a major unknown right now and goes into the heart of the module Tuner details, slow and fast, but especially fast tuner Vibrational analysis, which will be compared to measurements for verification of the model for future design work Development of module and module component test plans Verification of cavity positional stability with thermal cycles Design of test instrumentation for the module Robustness for shipping, analysis of shipping restraints and loads, shipping specifications Active quad movers(?) A complication

10. TTC Meeting Frascati Dec 5-7 Bernd Petersen Type IV probable schedule Design module -- 12 - 24 months (2006 - 2007) –Magnet/BPM package –Tuners, etc. –Integrate into module design Build and test -- 12 - 18 months (2007 - 2008) –In addition to module, need module test stand and test facility! Total 2 to 3 1/2 years, depending on scope of work and availability of resources.

11. TTC Meeting Frascati Dec 5-7 Bernd Petersen Type IV is not the (final) ILC design Test results of types III and IV will teach us a lot There will be some choices beyond type IV from parallel development efforts Industrialization will have a significant impact on the design Type IV is the next step in module design for ILC

12. TTC Meeting Frascati Dec 5-7 Bernd Petersen Discussions: Keep the components exchangeable for the different test facilities ! ( He pipes will stay in the present positions ) Quad for ILC is not yet defined All design changes will require the related tests

13. TTC Meeting Frascati Dec 5-7 Bernd Petersen Proposals to the test program to be carried out at DESY on the Cryomodule Test Bench and Cryomodule Test Facility Yury Bozhko DESY

14. TTC Meeting Frascati Dec 5-7 Bernd Petersen Cryomodule Test Bench (CMTB) Objectives: on the test bench complete system-tests of cryomodules have to be conducted aiming to finalize design of the XFEL–cryomodules and the related sub-systems Planning: the Test Bench will be commissioned in April 2006 first modules to be tested are either the Superstructure as a dummy in May or the Module 6 in June 2006

15. TTC Meeting Frascati Dec 5-7 Bernd Petersen Cryomodule Test Facility (CMTF) Objectives: testing all main components constituting the cryomodules as cavities and superconducting magnets qualifying all cryomodules after the assembly Planning: beginning of the construction - 2007 installation of the cryo- and RF equipment – middle of 2008 commissioning – middle of 2009 CMTF includes: three cryomodule test stands two vertical bath cryostats for testing single cavities one horizontal bath cryostat for testing SC magnets one horizontal cryostat for testing assembled cavities

16. TTC Meeting Frascati Dec 5-7 Bernd Petersen CMTB and CMTF: Common program for the cryomodules ‘standard’ test program without beam Mechanical check of components: alignment of beam tube, cryogenic tubes, coupler and vacuum flanges, feedthroughs etc., have to be checked. Leak tests of the vacuum systems (beam pipe, coupler and insulation vacuum) and cryo-pipes under He pressure Conditioning of the main RF-couplers (cavities off resonance) Conditioning with resonant cavities (check of tuning systems) Measurement of the dynamic cryogenic loads of the cavities to get the Q versus Eacc characteristics of the cavities and their maximum acceleration fields. Tests of the current leads of the SC magnet Static cryogenic heat loads will be measured at 40/80, 4.5 and 2K Monitoring of dark currents at one end of the beam tube of the cryomodules at both ends !

17. TTC Meeting Frascati Dec 5-7 Bernd Petersen CMTB specific tests: Displacement and vibrations measurements Displacements of the cold mass during and after cool down/warm up will be measured with the help of Wire Position Monitor system Prototype cryostats and the related systems will be extensively thermally cycled to investigate the influence on the performance of the modules. Novel generation of fast WPM electronics (INFN) would allow vibrations measurements CMTB specific tests: Thermal cycling CMTB specific tests: HPP processing Depending on the performance of the cavities in the module in comparison to the original tests results during the vertical tests of the individual cavities and depending on the onset of field emission, the cavities will be treated by HPP procedures.

18. TTC Meeting Frascati Dec 5-7 Bernd Petersen CMTB/CMTB tests (cond.) Special tests on CMTB: inclination, T- variations, venting…. Test program for sc magnets at CMTF Single cavity tests at CMTF

19. TTC Meeting Frascati Dec 5-7 Bernd Petersen CMTB/CMTF discussions Quad will only be tested at 4.5 K Main Couplers will be completely pre- conditioned before assembly to the module Standard test program was not questioned Dark current measurements are an issue !

20. TTC Meeting Frascati Dec 5-7 Bernd Petersen Preliminary results from TTF HOM BPM system TTC meeting, December 6, 2005 Marc Ross (SLAC) for Nicoleta Baboi, Rita Paparella, Olivier Napoly, Claire Simon, Joe Frisch, Tonee Smith, Justin May, Doug McCormick, Linda Hendrickson (DESY, Saclay, SLAC) and the TTF team.

21. TTC Meeting Frascati Dec 5-7 Bernd Petersen TTF HOM BPM system Purpose: –Find centers of cavities wrt each other Minimizing HOM power should improve beam dynamics (ACC1) –Augment existing BPM system; prove/disprove viability of HOM usage for BPM

22. TTC Meeting Frascati Dec 5-7 Bernd Petersen Signal –Dipole HOM phase and amplitude depends on offset and angle Alternatively ‘sine-like’ and ‘cosine-like’ trajectory distortion amplitudes, depending on phase definition.. –Basically ‘transit time’ effect –May find other distortions, but no evidence to date –Concern about damage caused by possible high power – installed additional 10dB attenuators. Should worsen resolution 3x

23. TTC Meeting Frascati Dec 5-7 Bernd Petersen Dipole Mode Response to Beam Note that centers (position / angle for zero signal) of HOM modes are modified by asymmetric couplers at the ~100 micron level

24. TTC Meeting Frascati Dec 5-7 Bernd Petersen Minimum power location – x – rms 420 um

25. TTC Meeting Frascati Dec 5-7 Bernd Petersen Minimum power location – y – rms 467 um

26. TTC Meeting Frascati Dec 5-7 Bernd Petersen

27. TTC Meeting Frascati Dec 5-7 Bernd Petersen Discussion HOM measurements will have to be continued for ACC4,5,6 and will be directly compared to WPM measurements Preliminary results acceptable for XFEL but not for the ILC This kind of HOM BPM measurements will be integrated in the ILCTA and STF facilities ( + WPMs)

28. TTC Meeting Frascati Dec 5-7 Bernd Petersen The Advantage of Having Beam at a Module Test Stand Hans Weise, DESY Working Group 3 TESLA Technology Collaboration Meeting Frascati, December 5 th - 7 th, 2005

29. TTC Meeting Frascati Dec 5-7 Bernd Petersen Advantages of having a beam on a module test stand Gradient check (RF measurement has +/- 10 % error) Effects of beam loading-> LLRF studies HOM excitation Check cavity alignment with beam HOM BPM method Precise measurement of dark current (use of spectrometer ?)

30. TTC Meeting Frascati Dec 5-7 Bernd Petersen Status of ILCTA@ Fermilab and plans for beam tests Sergei Nagaitsev Fermilab

31. TTC Meeting Frascati Dec 5-7 Bernd Petersen ILC Research and Development at Fermilab Two main branches: Develop world class SCRF expertise: module fabrication facility + module test facility “Reference Design Report effort”: machine design and site studies

32. TTC Meeting Frascati Dec 5-7 Bernd Petersen Beam test plans New Muon Lab – need a new name! FNPL Photo-injector Building a dedicated ILC cryomodule test in the New Muon Lab –Cleaning out building (Done) except for CCM –Plan is to install interim cryogenic solution in FY06 –Move FNPL Photo-injector to provide electron beam (Late FY06)

33. TTC Meeting Frascati Dec 5-7 Bernd Petersen Need to test things as far as possible in a realistic situation  need beam! Cavity gradient, gradient spread, dark current, cryogenic load, radiations levels with beam operation  Measure acc. gradient by measuring beam energy Evaluate performance of LLRF system: e.g. R&D on new algorithms; demonstrate 0.1% bunch-to-bunch energy spread over ~1 ms train HOM studies, including trapped modes; Reasons for beam tests (from SMTF meeting)

34. TTC Meeting Frascati Dec 5-7 Bernd Petersen Reasons for beam tests Beam-based measurement of component alignment and vibrations Possibly (?) measure single bunch wake-field effect in cryomodules Measure beam kicks due to couplers, cavity tilt, quad rotations + tilt errors characterize focusing properties of SCRF cavities

35. TTC Meeting Frascati Dec 5-7 Bernd Petersen Beam plan at STF phase1 12/6/2005 TTC-WG3 H. Hayano STF phase1 1st step : DC-gun + photo-cathode (2006) quick beam source( DC gun exist), no pre-acceleration, no buncher, but high density beam -> big space charge, bad transmission. 2nd step : RF-gun + photo-cathode (2007) similar to TTF, but heavy-load of laser development* RF-gun: easy extension of S-band RF-gun of ATF. *Laser development will be done continuously from step 1 to step 2. ** Why two step?: limited budget and man power, however need some beam to confirm cavity gradient in initial stage.

36. TTC Meeting Frascati Dec 5-7 Bernd Petersen Reason of Beam at STF To develop following performance & technologies; 1. Cavity gradient, 2. LLRF control for beam loaded cavities, 3. HOM studies for TESLA type and LL type, 4. Instrumentation (BPM, BSM) development, 5. Laser development for ILC beam generation, later, want to expand them to ILC Pol e- generation study*. (* Pol e- : by Nagoya-univ. and KEK collaboration)

37. TTC Meeting Frascati Dec 5-7 Bernd Petersen Define scope of module test-stand activities with and without beam Activities without beam Mechanical checks,RF,vacuum,cryo performance tests,dark-currents, special cryo-tests Activities with beam Gradient checks,beam loading LLRF, HOM BPM,dark-currents, cryo-loads, development of instrumentation