Commissioning of the Thomx SR Iryna Chaikovska LAL

Commissioning of the Thomx SR Iryna Chaikovska (LAL) on behalf of the commissioning group Programme Investissements d’avenir de l’Etat ANR-10 -EQPX-51. Financé également par la Région Ile-de-France. Program « Investing in the future » ANR-10 -EQOX-51. Work also supported by grants from Région Ile-de-France.

Lattice studies for Day 1 Lattice and parameters Tune, Chromaticity Tune shift with δp and amplitude Dynamic aperture Error analysis Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 2

Nominal Working Point 3. 17/1. 64 Ring lattice and parameters Thom. X SR: L = 18 m, T = 60 ns, Frep = 16. 7 MHz Parameter Value/Units Beam energy 50 -70 Me. V 24 Quadrupoles Bunch Charge 1 n. C 12 Sextupoles Bunch length (rms) 20 -30 ps Circumference 18 m 2 Kickers Revolution frequency 16. 7 MHz 1 Septum Current 16. 7 m. A RF frequency/Harmonics 500/30 MHz 1 RF cavity Momentum compaction 0. 0125 - 0. 025 12 BPM Betatron tunes 3. 17/1. 64 -9/-13 12 Correctors Natural chromaticity Damping time trans. /long. 1/0. 5 s Repetition frequency 50 Hz Beam size at the IP ~70 μm 8 Dipoles Nominal RF Voltage/cavity 300 k. V (500 k. V max) Energy loss per turn Thom. X Ring Commissioning 1. 57 e. V Thom. X Lattices Day 1 AT lattices: Thom. X_017_064_r 56_02_chro 00 Thom. X_017_064_r 56_03_chro 00 Thom. X_017_064_r 56_04_chro 00 Thom. X_017_064_r 56_02_chro 11 Thom. X_017_064_r 56_03_chro 11 Thom. X_017_064_r 56_04_chro 11 => check injection matching Iryna Chaikovska (LAL) – LAL, 18/12/2018 3

Tune (Working Point) and chromaticity 3 families of sextupoles (12 SEXT in total) Up to 4 th order SX 3 SX 2 Resonance condition: m*νx + n*νz = p Nominal WP: (3. 17, 1. 64) Alternative WP 1: (3. 16, 1. 58) Thom. X Ring Commissioning SX 1 Main chromaticity correction family: SX 2, SX 3 SX 1 can be used to adjust nonlinear chromaticity or tune-footptint Iryna Chaikovska (LAL) – LAL, 18/12/2018 4

Tune shift with δp and amplitude (multipole Higher order chromaticity errors) Nonlinear chromaticity is induced by multipole errors νx= 3. 17 νz= 1. 64 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 At higher values of momentum deviation δp or amplitude (X/Z) the tune footprint starts to approach the resonances The overall detuning stays reasonable for δp= ± 1. 5% and X = ± 15 mm/ Z= ± 10 mm 5

Dynamic aperture (multipole errors) βx@ injection: 3. 5 m βz@ injection: 2. 7 m DA at injection point DA @ δp= ± 1% • AT tracking. Nonlinearities of fringe field (DIPOLE, QUAD) and chromaticity SEXT included (linear chromaticity is corrected to zero) + Multipoles • The beam sizes can be estimated by εx, norm/ εz, norm = 7 -8 π mm. mrad and (εx/εz = 2. 7 e-7 - 3. 1 e-7 m. rad) => σx/ σz = 9. 7 e-4 (1 e-3)/ 8. 5 e-4 (9. 1 e-4) m • ON-momentum DA stays large enough compared to the physical acceptance of the SR @injection Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 6

OFF- Momentum dynamic aperture (multipole errors) DA at injection point OFF-momentum dynamic aperture under the SEXT effect, DIPOLE/QUADRUPOLE Fringing Field and Multipoles Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 7

Error analysis. Closed orbit/orbit correction. • 12 correctors for hor. /vert. plane in combination with 12 BPMs installed close to the quadrupoles • Machine imperfection assumed to follow Gaussian distributions. • The errors are assigned by pooling randomly from the truncated Gaussian distribution (2 sigma) • Orbit correction: SVD algorithm Min errors set (30μm/200μrad/1 e-3) BPM errors: • Offset errors: 200 μm • Gain errors: 1% • Reading errors: 100 μm • Rotation errors: 10 μrad Thom. X Ring Commissioning Max errors set (100μm/500μrad/5 e-3) Errors (rms) Δx [μm] Δy [μm] Tilt [μrad] Δs [μm] ΔKn/Kn Dipoles 30 -100 200 -500 30 -100 (1 -5)e-3 QUAD 30 -100 200 -500 30 -100 (1 -5)e-3 SEXT 30 -100 200 -500 30 -100 (1 -5)e-3 Iryna Chaikovska (LAL) – LAL, 18/12/2018 8

Sensitivity to machine imperfections Min errors set (30μm/200μrad/1 e-3) • • Orbit Max errors set (100μm/500μrad/5 e-3) Sensitivity of the closed orbit excursion to the individual error sources without any correction Most critical errors with respect to the closed orbit distortion are feed-down effects due to quadrupole misalignment Tilted dipoles induce mainly vertical and dipole field errors purely horizontal orbit distortion Quadrupole field errors and sextupole alignment errors can be neglected Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 9

Sensitivity to machine imperfections Min errors set (30μm/200μrad/1 e-3) • • Beta-beating Max errors set (100μm/500μrad/5 e-3) Sensitivity to optics distortion (beta-beating) caused by alignment and field errors of the main magnets Important contribution to beta-beating comes from the feed-down effects due to large closed orbit excursion in the sextupoles, as caused by the quadrupole alignment and dipole field errors Apart from alignment errors, the main sources for beta-beating are the errors in the quadrupole gradients Pure sextupole alignment errors are of minor importance Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 10

Sensitivity to machine imperfections Min errors set (30μm/200μrad/1 e-3) • • • Tune Max errors set (100μm/500μrad/5 e-3) Sensitivity to optics distortion (tune spread) caused by alignment and field errors of the main magnets Important contribution comes from the quadrupole gradients/alignment and dipole field errors Pure sextupole alignment errors are of minor importance Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 11

Impact of all error sources ALL errors together. Max errors set (100μm/500μrad/5 e-3) More close to Day 1 operation AT tracking (100 turns). Tracking starts at the injection point (middle of the septum) where βx@ injection: 3. 5 m βz@ injection: 2. 7 m and ηx @ injection: 0. 029 m Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 12

Correction of closed orbit ALL errors together. Max errors set (100μm/500μrad/5 e-3) 2 iterations, 10 SV 500 error seeds On average, orbit (max excursion) is corrected by a factor of ~ 7(hor)/5(vert). Can be optimized. Thom. X Ring Commissioning Distribution of the maximum corrector kicks for orbit correction. Max corrector strength@50 Me. V is ~5 mrad (Hor) and ~3 mrad (Vert) Iryna Chaikovska (LAL) – LAL, 18/12/2018 13

Ring Commissioning Inspired by commissioning organization at LHC Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 14

Thom. X commissioning stages Stage Objective HC Hardware commissioning TC Technical commissioning Beam Energy Charge Frep Bunch Length Energy Spread Emittance X-ray Energy X-ray Flux Beam commissioning (BC) A B Injector commissioning RF gun + Linac 50 Me. V 10 200 p. C 0 10 Hz 2 -8 ps 0. 2 -0. 4 % ~3 μm rad RF gun + Linac + TL + EL 50 Me. V 10 200 p. C 0 10 Hz 2 -8 ps 0. 2 -0. 4 % ~5 μm rad (inj) Ring commissioning 50 Me. V 200 p. C 0 10/50 Hz 2 -8 ps (inj) 0. 2 -0. 4 % (inj) Optimization of the IP 50 Me. V 200 p. C 0 50 Hz 2 -8 ps (inj) 0. 2 -0. 4 % (inj) D Commissioning at nominal charge RF gun + Linac + TL + EL + SR 50 Me. V 1 n. C 0 50 Hz 2 -8 ps (inj E X-ray production towards nominal operation Increasing X-ray flux to nominal 50 Me. V 1 n. C 50 Hz Commissioning and operation at 70 Me. V 1 n. C 0 50 Hz First turns + stored beam C F FPC commissioning + first X-rays Thom. X Ring Commissioning 2 -8 ps (inj Iryna Chaikovska (LAL) – LAL, 18/12/2018 1010 -1012 ph/s (@500 k. W) 11 10 -1013 ph/s LI: 5 μm rad RI: (@500 k. W) 45 ke. V max 7 -8 μm rad ~5 μm rad (inj) 45 ke. V max 7 -8 μm rad 15 45 ke. V max ~1013 ph/s (@500 k. W) 90 ke. V max ~1013 ph/s (@500 k. W)

Ring commissioning strategy Distinguish two forms of commissioning Hardware Commissioning/ Technical Commissioning Ø Acceptance tests of the equipment Done during initial commissioning and as part of the 'machine checkout' after technical stops Mainly done by system responsible/experts (almost finished) Ø Functional checks of the hardware Ø Checks conformity of the hardware control system and its readiness for beam commissioning/operation Should be done on a system-by-system basis Eventually more global approach should be applied Commissioning with Beam Ø Inject, thread, store and extract Ø Commissioning of beam-dependent equipment Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 16

Ring commissioning: checklist for the TC Installation is completed, alignment checked shortly before commissioning Injection/extraction system (septum + kickers) is tested Synchronization system is implemented and tested Radiation protection and safety systems are fully implemented Magnets are installed and checked (PS control, polarity…) Technical interlocks are tested Vacuum ideally 10 -10 mbar RF cavity is conditioned Feedback systems are installed and tested All Ring beam diagnostics are installed and tested All functionality tests are completed Control system is fully implemented and tested … Thom. X Ring Commissioning Different priorities and dependencies => input for the global Thom. X planning Can start the Beam Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 17

Ring commissioning with beam (phases) Phase B. 1 B. 2 B. 3 B. 4 C. 1 D. 1 F. 1 Description Injection and first turn: injection commissioning, threading, commissioning beam instrumentation Establish circulating beam: closed orbit, orbit correction, tunes, chromaticity Stored beam and extraction: precise measurements, BBA, feedback systems, beam diagnostics (SRM) Machine physics: LOCO, beta beating, beta function and dispersion, diagnostics, beam dynamics studies Operation with FPC and IP optimization: position and phase scan Ring commissioning at nominal charge: injection tuning and feedback test at the nominal charge, higher αp optics Ring commissioning at 70 Me. V: repeat the necessary commissioning steps (phase B) Beam Commissioning (BC) The detailed strategy was presented during the MAC in March 2017 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 18

Along with the Ring BC Equipment commissioning with beam Instrumentation commissioning Ø First turn i. e. immediately Ø BPM, BLM Circulating beam BPM, BLM, MRSV, Bunch Length Feedbacks Checks with beam Ø BPM polarity, corrector polarity, BPM response… Ø … Setting and test of the MML configuration and high level apps Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 19

Ring BC: phases description (template) Defined for each phase of Ring commissioning: Short description of what should be achieved Entry and Exit conditions definition of must-have systems/sub-systems List of systems to be considered “operational” afterwards Machine setup: Ø optics, beam type, diagnostics… Procedure: Ø detailed 'cookbook': check list of individual steps List of possible problems and first-order solutions Open questions/action items/references Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 20

Phase B. 1 short example (Injection and first turn) Short description of what should be achieved The injection will be done using the standard septum and one fast kicker set-up => single-turn on-axis injection. Once, the beam is injected, by tuning the correctors try to thread the beam and close the first turn. Entry and Exit conditions Entry: Injector delivers the beam with the sufficient quality (energy, charge, emittance, energy spread) + Injection matching Exit: the beam is injected on-axis. The beam is steered through the whole ring for first turn. Machine setup Quadrupoles, sextupoles, RF system, extraction kicker are OFF. Dipoles are ON. The dipoles are cycled to the same current as the TL dipoles. Diagnostics: BPM (sum signal and orbit), BLM. Procedure Scan of the septum and injection kicker voltage and timing. Observe the first signal on BPM. Perform the beam steering through the ring/beam threading. Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 21

Phase B. 1 short example (Injection and first turn) List of possible problems and first-order solutions Cannot thread the beam / beam lost somewhere Ø Causes: physical aperture (e. g. RF fingers…), misalignment, wrong magnet settings, polarity errors… Ø Diagnostic tools: BLM, BPM sum signal… Ø Solutions: local steering, realignment, element replacement… BPM errors make threading impossible Ø Causes: Polarity errors, calibration errors, cable inversions, electronic faults Ø Diagnostic tools: detailed analysis of the data, systematic polarity/calibration scans Ø Solutions : update the configuration, disable affected BPM, replace faulty equipment. Open questions/action items/references Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 22

Global Thom. X planning C. f. Denis talk The planning for the Ring will be revised in Jan 2019 Currently Ring BC can start in Oct 2019 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 23

Thom. X planning (Ring): 2 scenarious Scenario 1 SEPT + at least 1 KICK are tested/installed before May 2019 LI-TL-EL (June 2019) Scenario 2 SEPT + at least 1 KICK are tested/installed in ~Sept 2019 LI-TL-EL (June-July 2019) Baking the KICK VC Commissioning Ring (July 2019) Continue Ring (Sept-Oct 2019) Installation of the FPC (Oct/Nov 2019) Installation of the PE, FPC baking the KICK VC (Sept/Oct 2019) Commissioning Ring (Nov/Dec 2019 - Feb 2020) X-rays in spring of 2020 Critical elements: pulsed elements, especially kickers Max time consuming process: baking the VC~ 2 months and installation/tuning of the FPC (100 k. W) ~1 month X-rays in the beginning of 2020 *Scenario 3 “catastrophe” if the KICK are not ready => finalize the plan B Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 24

Phase B. 1 B. 2 Description Injection and first turns: injection commissioning, threading, commissioning beam instrumentation Establish circulating beam: closed orbit, orbit correction, tunes, chromaticity High Level Applications for the Day 1 (phases B. 1 and B. 2) Save/Restore machine configuration Calibration B(I) and Magnet Cycling First turns: trajectory correction First turns: orbit and orbit correction First turns: Tune First turns: chromaticity Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 25

Control system and high level apps TANGO is a global control system for Thom. X High level applications to control and measure the beam are developed by using Matlab Middle Layer (MML) Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 26

Matlab Middle Layer (MML) A goal of the MML is to provide a scripting language for machine simulations and online control (TANGO). Thom. X Ring Commissioning From MML doc Link between applications and control system or model Provide functions to access accelerator data AT model is good for debugging software without using accelerator Comes together with other physics libraries (LOCO, NAFF…) MML + AT + LOCO + TANGO cover many of the high level software concerns for storage rings and transfer lines. Iryna Chaikovska (LAL) – LAL, 18/12/2018 27

Save/Restore machine configuration Application to save/load the SR magnet settings (Machine <=> Simulator) Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 28

Calibration B(I) and Magnet Cycling DIPOLES QUADRUPOLES SEXTUPOLES >> gev 2 bend(0. 05) = 159. 2996 A >> bend 2 gev(300) = 0. 077 Ge. V HOR. CORRECTORS >> k 2 amp('QP 2', 'Monitor', 9. 9755, [1 2], 0. 05) = 3. 2596 A >> amp 2 k('QP 2', 'Monitor', 12, [1 2], 0. 05)=35. 2716 1/m^2 VERT. CORRECTORS k = B / Brho >> amp 2 k(’HCOR', 'Monitor', -10, [1 1], 0. 05) * Leff =5. 1 mrad >> amp 2 k(’VCOR', 'Monitor', -10, [1 1], 0. 05) * Leff =2. 9 mrad Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 29

Calibration B(I) and Magnet Cycling Dipoles During Ring tuning, a cycling procedure is required to obtain reproducible settings Total cycling time: ~20 min [so ~3 min for 0 to Imax, and the same for Imax to 0). Waiting time at Imax & I=0 ~30 sec. Quadrupoles Total cycling time: ~5 min [so ~1 min for 0 to Imax, and the same for Imax to 0). Waiting time at Imax & I=0 ~10 sec. Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 30

Calibration B(I) and Magnet Cycling Testing of the Cycling DS for the Thom. X Power Supply DS (fake) Simulations are done on tango-util 2 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 31

First turns: threading/trajectory correction At first turns Ø Conditions: quadrupoles, sextupoles, RF system, extraction kicker are OFF. Dipoles are ON Ø Beam will be lost after/near the IP => reading of 3 -4 BPMs in the single-pass mode (orbit and sum signal) Threading: one by one steering Automatic procedure for beam steering to facilitate the first turn commissioning under development Ø Thom. X Ring Commissioning Algorithm: selection of the most effective correctors located upstream of BPM to reduce the distortion of beam trajectory and steer the beam through the first turn of the SR. Iryna Chaikovska (LAL) – LAL, 18/12/2018 32

First turns: plotfamily application Once the first turns achieved => display application (e. g. orbit) Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 33

First turns: orbit and orbit correction Once the first turns achieved => orbit correction application Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 34

First turns: Tune To compute the tune => FFT of the turn-by-turn BPM data More sophisticated methods to increase the precision Ø FFT with zero padding (more accurate amplitude estimates) Ø FFT of turn-by-turn data convoluted with a sine window Ø NAFF (Numerical Analysis of the Fundamental Frequencies) Ø Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 … 35

First turns: Tune (4 -turn algorithm) Nominal WP: (3. 17, 1. 64) EPAC 94, Koscielniak, pp 929 -931 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 36

Simulated turn-by-turn data (with noise added) Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 37

First turns: chromaticity Once the first turns achieved => chromaticity measurements measchro application Thom. X_017_064_r 56_02_chro 00 Thom. X Ring Commissioning Thom. X_017_064_r 56_02_chro 11 Iryna Chaikovska (LAL) – LAL, 18/12/2018 38

Phase B. 3 B. 4 Description Stored beam and extraction: precise measurements, BBA, feedback systems, beam diagnostics (SRM) Machine physics: LOCO, beta beating, beta function and dispersion, diagnostics, beam dynamics studies High Level Applications for Phases B. 3 and B. 4 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 39

Examples of applications Optical functions measurement RM measurements Lattice symmetry restoration (LOCO) BBA Closed orbit bumps … Work ongoing to finalize and test the applications for the following phases B. 3 and B. 4 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 40

Summary-Perspectives Linear lattice of the Thom. X SR provides good tuning flexibility which is important for the commissioning. Different lattices (R 56, chromaticity) are prepared for the commissioning and operation. Lattice studies (sensitivity to machine imperfections, DA, tune shift with δp and amplitude) are performed and show the possible situation expected during the SR commissioning. Ring commissioning procedures for every phase to be written down (available in the control room). The global planning of the Ring commissioning will be revised in the beginning of January. Finalize High Level Applications for the phase B. 1 and B. 2 Continue work on the High Level Applications for the phase B. 3 and B. 4 Thom. X Ring Commissioning Iryna Chaikovska (LAL) – LAL, 18/12/2018 41