1. RF and Transverse Dampers Current Systems Wolfgang Hofle W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 1 Acknowledgements: RF group, Section Leaders and Deputies Special Thanks to L. Arnaudon, P. Baudrenghien, A. Blas, T. Bohl, A. Butterworth, H. Damerau, F. Gerigk, P. Maesen, E. Montesinos, M. Paoluzzi, C. Rossi, D. Valuch, U. Wehrle Disclaimer: 15 minutes to cover … 2035

2. W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 2 Accelerators and Projects involving RF (1) Types of electronics: PLC, analogue (A), digital (D), RF power (P)

3. W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 3 Accelerators and Projects involving RF (2) Types of electronics: PLC, analogue (A), digital (D), RF power (P)

4. RF waveguide Arc Detector (1) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 4 D. Valuch et al. This is also a Technology Transfer Project protects  transmission line system  sensitive RF elements (ceramics, ferrites)  based on optical detection currently deployed system in LHC  optical fibers suffer radiation damage  interlock logic to mitigate spurious triggers put in place, no more problem in 2012 run new system, being deployed in LINAC4 gradually to be migrated to LHC  no fibers  four redundant detectors, voting logic  “sun glasses” to blind-out showers  future rad testing envisaged to level expected for HiLumi  needs to be in tunnel  alternative: acoustic detector current new spurious triggers rad damage

5. RF waveguide Arc Detector (2) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 5 detector box logic box  new arc detector deployed in LINAC4  reliability testing in LINAC4  many outside labs expressed interest  manufactured in industry under license  future radiation testing envisaged  need estimate of dose rate in tunnel for HiLumi era close to cavities

6.  “Finemet” is a magnetic alloy  high permeability  potential to replace ferrite based cavity systems in injectors by wideband systems without need for a tuner LIU project proposes:  a finemet based system for PSB (replacing the C02 and C04 RF tetrode systems)  a wideband long. damper for PS Solid state amplifiers for Finemet Cavities PSB RF and PS long. damper (1) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 6 „Finemet Review“ 9-10 September 2014 (LIU) http://indico.cern.ch/event/315998/timetable/#20140909.detailed  series of ceramic gaps  powered by individual amplifiers  modular design  fast feedback requires proximity to cavity and beam  electronics exposed to radiation M. Paoluzzi et al.

7. Solid state amplifiers for Finemet Cavities PSB RF and PS long. damper (2) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 7 „Finemet Review“ 9-10 September 2014 (LIU) http://indico.cern.ch/event/315998/timetable/#20140909.detailed  design of amplifier in house at CERN  based on experience with transistor in similar applications  drift of bias characteristics compensated by circuit to mitigate ageing by radiation  radiation tests at JPARC (Japan) and Fraunhofer Institut in Germany  solution with Shielding has been studied and deployed for SS02 in PS  tube amplifier would be alternative … but design with many gaps adapted to solid state amplifiers  tubes used in LEIR and JPARC (Japan)  collaboration with JPARC for solid state system integrating effect of radiation compensating circuit being tested shielding PS SS02 for long. damper cavity amplifiers

8. Solid state amplifiers for PS-RF (40 MHz & 80 MHz) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 8 Annexes for electronics And feedback amplifiers

9. Solid state amplifiers for PS-RF (40 MHz & 80 MHz) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 9 Doses in Gy

10. Solid state amplifiers for PS-RF (40 MHz & 80 MHz) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 10 Shielding put in place (LS1)

11. Pick-up electronics in tunnel (PSB, PS, SPS LSS3) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 11 PSB (RF resp.) head amplifiers transverse feedback RF loops regular maintenance PS (BI resp.) head amplifiers transverse feedback RF loops SPS LSS3 Beam observation equipment, RF pick-ups if re-design more rad. monitoring may be needed to get levels for specifications Example: SPS pit equipped with Beam Observation equipment in SPS LSS3 (U. Wehrle)

12. Pick-up electronics in tunnel (SPS Damper LSS2) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 12 electro-static PUs with high impedance preamplifiers in tunnel LS1: electronics moved from 208, 209, 210, 211 to newly installed PUs at 202, 204, 205, 207 all checked and repaired (R. Louwerse/G. Kotzian) spare electronics remains in tunnel (hot spares) @212, 213, 214, 215 pit equipped with damper electronics for fixed target beam, very reliable & robust (20+ years) (future renovation envisaged, outside LIU scope) 100 MHz bandwidth, discrete transistors power supplies need regular changing rad monitoring radiation before redesign ?

13. High bandwidth Feedback Solid State Amplifiers in LSS3 of SPS (1) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 13  R&D project to demonstrate damping of headtail motion in SPS (e.g. ecloud)  funded by LARP and LIU SPS  decision in 2016 on full deployment  solid state amplifiers 4x100 W installed since 2011 under QD319  driving BPW pick-up as kicker  radiation damage to power supply mitigated by change of power supply  powering of amplifiers only during MDs tunnel

14. High bandwidth Feedback Solid State Amplifiers in LSS3 of SPS (2) W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 14  new amplifiers for next stage  jointly with SLAC selected amplifiers from R&K Japan (4x200 W)  Installation in tunnel to power new kickers  radiation measurements ongoing to decide on installation location  later stage (>2016) if full system deployment  more amplifiers  need for proper radiation measurements, testing, calculations, started existing amplifiers (QD319) new stripline kickers in 321

15. LHC: Summary of equipment underground W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 15  Tunnel:  Cavities with arc detectors  ADT tetrode amplifiers (considered robust)  APW pick-ups (re-design due to losses for HighLumi ?)  Cryo side of UX45:  beam observation equipment for long. plane  digitizers, VME hardware, timing, fiber optic links  relocation to ex-LEP klystron gallery for HiLumi era  Cavern side of UX45 considered ok:  Klystron related drive and controls  Faraday Cages with fast feedbacks and cavity tuning  ACS cavity controls  ADT drive and control layout is result of radiation simulations, e.g. LHC Project Note 342 all radiation issues needs re-consideration for HighLumi era measurements also would be highly appreciated, deploy in EYETS ?

16. LHC point 4 – UX45 cavern W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 16 Radiation sources: X-rays from cavity conditioning Beam-gas interaction chosen location inside Faraday cages rack location Beam observation relocation for HighLumi 24 m 5 m two shielding walls + chicanes Klystron related Faraday Cages LLRF, feedbacks ACS cavity PLCs ADT drive/PLCs APW observation arc detectors

17. Availability – LS1 W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 17 See P. Maesen at 2013 Workshop on Availability and Dependability availability of RF in run 1 not driven by R2E  part of big 4 for lost Physics hours mitigations in place and being followed-up for non-R2E ACS (400 MHz RF)  arc detectors (this was R2E)  crawbar, new development, see G. Ravida et al., IPAC’12 THPPD056  klystron filament current: bad HV cables, connector weldings  ACS Module exchange, driver amplifiers  klystrons exchanged and klystron cooling fixed ADT (transverse damper)  cabling replaced  electronics upgrade, electrical contacts  power system maintenance and fixes, air cooling improved  new water cooling interlocks  vacuum interlocks SR4 air conditioning and temperature stabilization in RF zone (roof)

18. Summary and final thoughts W. Hofle - RF+Dampers - R2E and Availability Workshop 14-17 OCtober 2014 18 most of R2E issues for RF are in injectors, need follow-up R2E in injectors not related to HighLumi LHC (radiation driven by non-LHC beams) impact of R2E on availability in injectors if failure of equipment UX45 cryo side equipment likely needs re-location for HighLumi era document evolution of radiation levels in UX45 with measurements with RF and LHC, LHC RF caused a significant number of lost hours during run 2 driving problems for LHC RF availability haven been addressed in LS1 on time horizon of 2035 ageing of material related to radiation has to be addressed through consolidation continuously availability tracking tool highly appreciated only the tedious search & elimination of root causes will increase availability worth to re-check 2012 RF faults statistics in LHC (more time needed)