1. U. Iriso ESLS XXIII Nov. 2015 Commissioning of the Bunch By Bunch Feedback System U. Iriso, J. Moldes, A. Olmos (ALBA – CELLS) M. Abbot, G. Rehm (Diamond)

2. U. Iriso ESLS XXIII Nov. 2015 Outline BBB Layout BBB Commissioning System Features

3. U. Iriso ESLS XXIII Nov. 2015 Libera FrontEnd Libera BbB IFI 100W ampli Hybrids Button BPM Stripline Kickers 100W atten Scope BbB Layout

4. U. Iriso ESLS XXIII Nov. 2015 BbB Layout (2015) BPM FFK - Y FFK - X BbB - Y Timing EVR BbB - X Clk2 - 500MHz Clk1 - 500MHz Xout Yout A B C D 100W Att Load Scope Load Scope 100W Att Load Scope Load Scope 500MHz ALBA Master Clock RF FE 100 W Hybrids Four Amplis Configuration

5. U. Iriso ESLS XXIII Nov. 2015 BbB Layout (2016) BPM FFK - Y FFK - X BbB - Y Timing EVR BbB - X Clk2 - 500MHz Clk1 - 500MHz Xout Yout S180-HP A B C D 100W Att Load Scope Load Scope 100W Att Load Scope Load Scope 500MHz ALBA Master Clock RF FE Hybrids 100 W Two Amplis Configuration + High Power Splitters

6. U. Iriso ESLS XXIII Nov. 2015 100W Ampli LPF [0 - 300]MHz (to protect amplis) S180-HP BbB Layout (2016) New Hardware at ALBA – ready to test

7. U. Iriso ESLS XXIII Nov. 2015 Outline BBB Layout BBB Commissioning System Features

8. U. Iriso ESLS XXIII Nov. 2015 Diamond colleagues offered a collaboration to port Diamond TMBF to ALBA system Main steps: * HW checks/modifications on Amplifiers, Hybrids and phase matching of cables * Migrate the full FPGA code from SystemVerilog to VHDL language * Adapt it to ALBA machine (harmonic number, revolution frequency, tunes, …) * Install an “EPICS worm” (EPICS Base) inside our Tango control room * Build libca library to transfer data to Matlab * Permanently install Diamond TMBF code in our Liberas BbB (“brain” washed) We did a not very successful try with I-Tech Matlab interface TMBF Commissioning with beam with M. Abbot and f G. Rehm (May 2015) BbB – Diamond TMBF Commissioning

9. U. Iriso ESLS XXIII Nov. 2015 Phase Offset Optimization (Mixer) PhaseX=20deg ; PhaseY=-20deg Hor Ver BbB – Diamond TMBF Commissioning RF FrontEnd X/Y outputs Need to maximize the signal to have the highest levels at Libera BBB

10. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Commissioning Amplifiers characterization 50dB gain – quite flat over all interesting freq range [0-250]MHz [0-200] MHz,  ~10deg  ok Clear degradation occurs >200MHz One of the amplifiers broke, so we could only install the BBB in the one plane (ver)

11. U. Iriso ESLS XXIII Nov. 2015 Single Pulse from Libera BBB + Ampli + Kickers + Attenuators The amplis distort the signal, produces a ripple of ~6ns  We will not kick a single bunch, but alsoadjacent bunches! In the near future, we plan to exchange our amplis Single Pulse (2ns) from Libera BBB BbB – Diamond TMBF Commissioning

12. U. Iriso ESLS XXIII Nov. 2015 Synchronize BBB pulse with bunch passage (single bunch) BBB Pulse + delay + 1ns cable Bunch Passage BbB – Diamond TMBF Commissioning Fine phase delay tuning adjusted adding short cables in the loop: 300ps, 500ps, 1ns

13. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Commissioning FIR Phase adjustment with stable beam Tune Phase ~ +/-180deg Decrease usual chroms and switch on BBB…  It works!! BBB OFFBBB ON

14. U. Iriso ESLS XXIII Nov. 2015 DCCT and beam size evolution during first switch On Inject 100mA, uniform filling, chroms = (1.6, 0.2) BbB – Diamond TMBF Commissioning 30min

15. U. Iriso ESLS XXIII Nov. 2015 Outline BBB Layout BBB Commissioning System Features

16. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features Diamond TMBF allows to: Setup different “Banks”: ways to act on the beam (damping, excitation, sweep…) Combine them with the “Sequencer” This can produce interesting features (see next, and also Guenther’s ppt at DEELS14 )

17. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features 1.Get a stable beam using TMBF 2.Excite mode m 3.Measure the growth time 4.Switch TMBF back on for that mode 5.Measure damping time 6.Damp again mode m, and repeat for m+1 Unstable modes identification Prepare the following sequence:

18. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features Unstable modes identification Excitation Mode m Growth rate, 1/turns Damping No Damping RW ?

19. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features Bunch Cleaning: Define a backwards sweep around Qv Activate DAC only in buckets B77 & B80 Killed B76, B77 Killed B79, B80 Killed in previous tests Before BC After BC

20. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features Bunch Cleaning: Easier to clean a single bunch! Parasitic bunches are produced by the Linac with 18ns delay!?

21. U. Iriso ESLS XXIII Nov. 2015 BbB – Diamond TMBF Features Tune Measurement using PLL: Measure beam phase response to an input freq (needs to be very close to Qv) Keep track of frequency (tune) change to match phase  Q ~ 1e-5! Input signal needs to be very small, compatible with normal operation In this case, one measurement/200 turns Applied only to single bucket

22. U. Iriso ESLS XXIII Nov. 2015 Frequency, Hz FFT Amplitude Measurement taken with ChromV~0 FFT of a BPM buffer of 2.5e5 turns BbB – Diamond TMBF Features Tune Measurement using PLL: Main tune jitter peaks at 100 and 300Hz Compatible with tune jitter measurements with other means:

23. U. Iriso ESLS XXIII Nov. 2015 BbB – Conclusions Diamond TMBF has been commissioned at ALBA Quite easy and straight-forward (thanks to Guenther and Michael!) An “EPICS worm” has been installed in our Tango-based Control Room Diamond TMBF allows several interesting features, already tested at ALBA: o Sequences to identify unstable modes o PLL tune tracking with 1e-5 precision (compatible with machine operation!) So far, only commissioned in the vertical plane due to hardware (ampli) failure.

24. U. Iriso ESLS XXIII Nov. 2015 http://www.ibic2016.org/ Thank you and see you soon!

25. U. Iriso ESLS XXIII Nov. 2015 BBB – Extra slides

26. U. Iriso ESLS XXIII Nov. 2015 Commissioning procedure * Finding proper RF FE settings (phase offset, clock phase, …) * Problem in Hybrids X signal * BbB “brain washing” failed  processor board already reflashed at Diamond * Ugly single pulse out of the amplifier. That will affect adjacent bunches * 2ns jump of the single pulse out of one BbB unit. Diamond has reproduced the problem in their lab (DAC initialisation) * Change ALBA timing to TMBF needs * Aligning system to the bunches @ machine SBM * Inject 100mA uniform filling beam * Vertical loop closed just by setting the feedback phase * Chrom reduced to ‘0’ and beam kept stable * Bunch cleaning test: - no bunch kicking until scrapper closed - 2 bunches kicked out because of ampli * Unstable modes identification (m=-8) *

27. U. Iriso ESLS XXIII Nov. 2015 Extra slides: 2ns jumps Scope in persistence mode, to show the 2ns jump (green). The violet trace is the trigger.

28. U. Iriso ESLS XXIII Nov. 2015 Extra Slides: ADC offsets Fixed w.o. beam, just using the GUI capabilities