Olivier Brunner, on behalf of RF/MK.

1. Olivier Brunner, on behalf of RF/MK. RF/MK: 2013 in a nutshell

2. Linac 4 – HPRF system installation and commissioning • Installation: equipment, waveguides, water cooling, local cabling • Upgrade of LEP equipment • Contract follow up: new klystrons, spare circulators • Reliability is a key issue here: RFQ commissioning, phase adjustment

3. Developments • graphic user interfaces (GUI) • phase adjustment / phase tuners WR 2300, L = 1500 mm, r1=70mm, r2 = 40mm VSWR ≈ 1.2 [depth 0 -> 100 mm] S11 ≤ -30 dB [depth 0 -> 90 mm] Range: ≈ max 60˚

4. LHC RF System Operation (ACS) D. Glenat • System performed very well: Did not limit the evolution of peak or integrated luminosity • Better performance than in 2011 • Some “weaknesses” have been identified To do list 8 klystrons replaced (new boilers + age profile) HV bunkers equipped with new air cooling systems New klystron heating system Oil tests and reconditioning HV cable repair campaign Thyratron replacement DCCT and tetrode replacement R&D in progress Maintenance …

5. Solid state crowbars (“fast protection system”) • Sophisticate circuit • Water/oil Cooling • 350 litters oil volume • Limited lifetime • Very simple circuit • No cooling (±10W) • 90 litters oil volume • Solid State device has better performances than the thyratron • Validated during 2012 running period • In series production

6. Repair of the high voltage connectors Zone with welding defect • Klystron filament glitches responsible for frequent RF trips during operation • Procedure validated to re-weld the connectors without damaging the insulation material • Campaign in LHC will soon be launched

7. Digital measurement system for the klystron modulators Zone with welding defect • Equipment used in LHC are no longer produced by industry • Development of a FPGA based electronic located in HV modulator • Evaluation tests in progress

8. A new generation of Arc Detectors for the HPRF systems Zone with welding defect • Presented at the BE-KT day, June 3rd2013 • Agreement between CERN and an external company (Microstep-MIS- Slovak Rep.) to transfer the knowledge

9. SRF research Sample Testing with the Quadrupole Resonator • Testing of models for SRF loss mechanisms • Studies of new materials and niobium treatments High resolution measurements of the surface resistance Research Highlight: Slow cooling across Tc mitigates flux trapping in bulk niobium and reduces its residual losses.

10. CTF3 & CTF3 Test Beam Line (TBL) TBL line in CLEX Beam deceleration, measured in spectrometer and compared with expectations Zone with welding defect • CTF3 operation (11 S Band and 1 L Band power sources) • Thirteen PETS tanks installed and commissioned • Full beam transport to end-of-line spectrometer • Power produced (70 MW/PETS): fully consistent with expectations • Max power produced: 720 MW (12 PETS) • Max deceleration: ≈ 36%

11. Drive beam front end developments Zone with welding defect • Contract (almost) placed with industry for 1 GHz high efficiency klystron • Gun • Sub-harmonic buncher • Beam dynamics

12. Xbox1: 12 GHz high gradient breakdown tests • Xbox1 reliably working for most of the year • Two structures successfully tested • Test bed for: • LLRF systems • Conditioning and breakdown detection algorithm • Diagnostic tool development Zone with welding defect Test Stand produces reliable results comparable to KEK

13. Preparation of Xbox2 Zone with welding defect • Xbox2: Second X-band test bench in bld 150 • Modulator installed • Klystron in validation tests at SLAC • Commissioning: Spring ‘14

14. Next generation of x-band facility: Xbox3 Zone with welding defect • Based on high repetition, low power klystrons • Contract for klystron&modulators placed in August (Toshiba) • Integration work has started

15. LEP Copper cavities – a new life! London Science Museum CERN, Bld 182 Zone with welding defect • Cavities shipped to: • Pakistan, London, Edinburgh, Madrid, Rome, Berlin, Poland, Norway, Hungary, Denmark, Cern,...