1. Feedback and Beam Control Section (FB) Activities and Highlights 2014 Outlook Wolfgang Hofle FB Section at 2014 RF Group Meeting - December 2014 1

2. 2 Feedback and Beam Control Section Involved in most accelerators 20 staff members, 2 Fellows, 1 COAS (December 2014) Visitors from collaborations Responsibilities Operation of feedback systems Machine development work Conceptual design of RF and feedback system Design of hardware and FPGA firmware Project follow-up Collaborating with all sections of the RF group SRF, BR, CS, LRF, MK, PM, IS Despite many slides: Please forgive me if your favourite project is not included Many thanks to all the colleagues who provided me with input to this presentation … I had to shorten some of the input …

3. FB Section at 2014 RF Group Meeting - December 2014 3 Coming out of LS1 - Start-up 2014 PSB PS LEIR AD SPS Naturally a lengthy start-up and short Accelerator Run CTF3, XBOX, SM18, LINAC4 !

4. RF group meeting 2014 Linac4 LLRF J. Noirjean, J. Galindo, D. Stellfeld, G. Hagmann, P. Baudrenghien, M. Ojeda May 2014 Cavity Filling Ramp (50  s) Feedback On Zoom  Installed on RFQ, Bunching cavities 2-3, DTL1  Observed ripple: 0.06% voltage, 0.05 deg, without beam  Transient beam loading: 1% voltage with 8 mA beam  Pulse to pulse reproducibility: +- 0.05 deg

5. FB Section at 2014 RF Group Meeting - December 2014 5 New PSB Digital LLRF system Four operational Digital LLRF systems (Ring 1 to 4) + development ring (ring 0) which operates Ring 4 beams in PPM with Ring 4 DLLRF. Big RF group investment (manpower) for Meyrin machines. PSB operational LLRF after LS1 Mandatory for PSB Finemet R&D campaign (2014-2015). Will be deployed in LEIR in 2015 and in ELENA in 2016. The hardware The people The results

6. DLLRF operation for PSB Finemet R&D PSB Finemet tests started in 2014: “Ring 0” DLLRF controls voltage (amplitude + phase loop @ 4 harmonics so far) in 10-cells Finemet cavity installed in PSB ring 4 (up to 7 kV). ~ 800E10 protons accelerated with Finemet as C02 (@h=1, 7kV) + C02 (2.3kV) & C04 (8 kV). 650E10 protons accelerated with Finemet alone as C02 (@h=1, 7 kV). 790E10 protons accelerated with C02 (8 kV) + Finemet as C04 (@h=2, 7 kV) + C16. Finemet used as C04: Finemet alone: Finemet used as C02:

7. FB Section at 2014 RF Group Meeting - December 2014 7 CERN-MedAustron collaboration (HLRF + LLRF) Successfully delivered & contributed to commission Digital LLRF (PSB-style) + HLRF (Finemet-based ) systems for MA synchrotron. MA milestones so far: LLRF team to keep supporting MA Ring RF system when possible.  26 May ‘14: first capture  20 Oct ‘14: first extraction to IR3 @62.5 MeV  6 Nov ‘14: 10E8 protons extracted to IR3 @250 MeV MedAustron synchrotron Irradiation Room 3 (IR3) MedAustron complex M. E. Angoletta, M. Jaussi, J. Molendijk, M. Paoluzzi, J. Simonin, J. Sanchez Quesada

8. RF group heavily involved in ELENA RF workpackage: Schottky longitudinal PUs (ring + transfer lines) & data processing HLRF (Finemet) Digital LLRF. ELENA technical design report published in 2014. Good progress so far but lots to do in 2015. First beam: April 2016!! AD to be consolidated after ELENA and to profit from ELENA’s developments. FB Section at 2014 RF Group Meeting - December 2014 8 ELENA and AD

9. FB Section at 2014 RF Group Meeting - December 2014 PS – RF Controls Renovations 9 During… Completed  Commissioned and fully operational since start-up 2014 New controls front-ends for PS beam controls Part of ACCOR Project: collaboration with CO group Relocation of equipment Digital distribution of voltage programs  new ‘matrix’ for 10 MHz system V prog V det Loop error RF gap 500 mV/div 200ms/div 100 mV/div 5 mV/div LHC25NS_12b 10 MHz AVC H. Damerau, V. Desqiens, D. Perrelet

10. FB Section at 2014 RF Group Meeting - December 2014 PS: Performance with 1TFB 10 Almost nominal intensity 1.3·10 13 ppp FB off FB on G FB = 2 Gap relays open + 1TFB off Zoom on beam induced voltage 1TFB on H. Damerau, S. Hancock, D. Perrelet PS AD beam batch compression

11. RF group meeting 2014 SPS LLRF – frequency program  New frequency program ◦ Replaces the module installed in 1998 (that replaced a 1983 module…) ◦ Full ppm operation  Upgraded Master DDS for ions ◦ Reduced RF noise. The triangular shape of bunch intensity and bunch length along the SPS batch was traced to IBS and RF noise during the long SPS injection plateau ◦ Should be better in 2015… A. Pashnin, J. Bento, D. Stellfeld, J. Noirjean, P. Baudrenghien J. Bento, D. Stellfeld, T. Bohl, P. Baudrenghien Bunch length in the LHC after Pb filling, M. Schaumann, BE-ABP, presented @ LMC Feb 13 th, 2013

12. FB Section at 2014 RF Group Meeting - December 2014 12 Ar-Ion beams: a challenge from LEIR to SPS via PS f rev Ar 11+ B-train reception for PS Ar frequency program using “White-Rabbit” Ions are always special, and Argon is even more special ! Modulation of RF at 4xf rev for Ar capture in SPS FSK and AM of RF In FB Section for longitudinal plane: M. E. Angoletta, P. Baudrenghien, H. Damerau, J. Ferreira, A. Findlay, D. Perrelet, U. Wehrle RF(AM) FSK beam Bdot

13. FB Section at 2014 RF Group Meeting - December 2014 PS,PSB,AD,LEIR – Transverse Feedback 13 PLC in the PSB -> identical in PS, LEIR, AD David 2 + Luca PSB water cooling -> identical in PS, LEIR, AD Ali Dridi Safer water distribution with better diagnostic and control All the PS, PSB, AD and LEIR damper’s cooling system rebuilt and connected to a PLC system Water leak detection and automatic shut-down. New LL and power electronics to be delivered in the transverse feedback systems of the PS and PSB in 2015 Better diagnostic and control of power equipment: All the PS, PSB, AD and LEIR damper systems equipped with PLC control Better monitoring: All the PS, PSB, AD and LEIR dampers connected to OASIS Ready for the L4 era in the PSB: 15 racks reinstalled and ready for the upgraded electronics AD damper system entirely moved to a more convenient location with a total re-cabling A. Blas, A. Findlay, R. Louwerse

14. FB Section at 2014 RF Group Meeting - December 2014 SPS – Damper (transverse feedback) 14 G. Kotzian, T. Levens, D. Valuch A. Rey, Y. Le Borgne 4x new Board 120 MHz clocked

15. Dec 12th, 2014 RF group meeting 2014  One-Turn delay feedback added on TWC800MHz Cavity 1 for compensation of transient beam loading  3 MDs performed in Autumn 2014 LIU SPS: LLRF for 800 MHz TWC (1) G. Hagmann, P. Baudrenghien, D. Valuch, S.J. Calvo  Cavity Vector sum (37 cells)

16. RF group meeting 2014 LIU SPS: LLRF for 800 MHz TWC (2) G. Hagmann, P. Baudrenghien, T. Bohl, M. Ojeda, A. Rey, F. Killing, J. Noirjean  Amplitude and phase of measured cavity voltage (800MHz)  Very effective compensation of the transient beam loading  RF (800MHz) demod to IF (25MHz)  ADC’s & Digital IQ (BW=12MHz)  FPGA:100MSPS signal processing  DAC’s & SSB Modulator to RF  ≤3.2Gbits/s links (SFP) Nov. 26 th, 2014 Feedback Gain=1 Feedback Gain=25

17. RF group meeting 2014 HiLumi LHC WP4: Crab Cavities (CC)  Transverse emittance growth caused by CC RF noise can reduce the integrated luminosity much  Formulas have been derived for the effect of phase and amplitude noise, with and without transverse feedback  The dominant noise comes from the LLRF demodulator that must be improved: target=-149 dBc/Hz @ 3 kHz offset. For all betatron bands, the demodulator noise dominates the TX noise (filtered by cavity). 100 kHz regulation band T. Mastoridis, P. Baudrenghien

18. FB Section at 2014 RF Group Meeting - December 2014 18 D. Valuch, M. Elias, M. Mician HIE Isolde LLRF Installation HIE Isolde only 16 meters long, but 32 superconducting cavities challenge to control the cavity, only few Hz bandwidth, all field changes have to be super- adiabatic in order not to lose the cavity due to Lorentz force detuning LLRF entirely digital, direct RF sampling, direct RF generation 32 solid state RF amplifiers, 700 W each Traditional Faraday cage replaced by “Racks Faraday” Linac cabling campaign finished November 2014 commissioning planned to start in summer 2015 “Racks Faraday” Linac “tunnel” Power amplifier racks

19. FB Section at 2014 RF Group Meeting - December 2014 19 LS1: LHC LLRF: SR4 enclosure  Enclosure of the LHC LLRF zone in SR4 (Beamcontrol, ADT, Beamobservation)  Private AC system with regulation of temperature and humidity  Decided in 2007…realized in 2014  A/C under commissioning D. Stellfeld, EN-CV, EN-MEF, EN-EL Shutdown coming to an end for LHC, too

20. FB Section at 2014 RF Group Meeting - December 2014 20 LHC Damper – ADT – preparations for Run II G. Kotzian, D. Valuch Injection of LHC beam Stable bunches oscillating bunches Transverse oscillations from ADT I (400 MHz) Q (400 MHz)

21. FB Section at 2014 RF Group Meeting - December 2014 21 LHC LLRF: controlled noise injection  Studies on the use of colored noise to shape the longitudinal bunch profile (heating, stability and longitudinal blow-up)  LHC RF phase noise generation, phase loop, and bunch length feedback implemented in the BLonD code  First simulations of controlled longitudinal emittance blow-up during the ramp confirm a rounder bunch core and low tail population H. Timko, E. Shaposhnikova, P. Baudrenghien Initial Final

22. FB Section at 2014 RF Group Meeting - December 2014 22 FB Section Significant contributions cont. CTF3: exploitation XBOX: structure testing Preparation of AWAKE (Plasma Wakefield Acceleration) R&D for GHz transverse feedback in SPS Many Thanks to all ! Stay tuned for 2015 Highlights !