1. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 1 Femtoslicing at SOLEIL M. Labat, M.A. Tordeux, M.E. Couprie, A. Nadji, P. Hollander, P. Prigent, J. Luhning, P. Morin, J.B. Brubach, P. Roy, C. Laulhe, P. Fertey, A. Ciavardini, M. Silly, F. Sirotti.

2. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 2 Storage rings : –= Synchrotron Radiation source In insertion devices (undulators) In bending magnets –Typical pulse duration : few tens of ps –Large range of experiments: … Time-resolved experiments Introduction  Need always shorter pulses…

3. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 3 Ultra-short pulse generation methods: –Coherent Harmonic Generation [ J.M. Ortega, NIMA250 (1986) ] –Crab cavities [A. Zholents, NIM-A, 425, 385 (1999) ] –Low-alpha mode –Femtoslicing [ A.A. Zholents, Proc. of the PAC’07, 69-73 (2007) ] Introduction

4. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 4 Ultra-short pulse generation @ SOLEIL: –Low-alpha mode : >> in operation since 2010: delivery of few ps pulses –Femtoslicing : >> under commissioning since 2014: expected delivery of 100 fs pulses Introduction

5. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 5 Femto-slicing concept [1] A.A. Zholents, Proc. of the PAC’07 Conference, Albuquerque, New Mexico, USA, 69-73 (2007). From R. W. Schoenlein et al., Science 287, 2237(2000). Schematic of a femto-slicing [1] experiment:

6. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 6 1 – Change the electron energy only within a tiny slice 2 – Use dispersive element to separate the slice from the core IR laser E- beam Femto-slicing concept v No energy exchange E v Energy exchange Inside a wiggler magnetic field  bending the e- beam trajectory… under resonance condition: λ laser = λ wiggler E. v ≠ 0 E. v = 0

7. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 7 1 – Change the electron energy only within a tiny slice 2 – Use dispersive element to separate the slice from the core Femto-slicing concept

8. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 8 1 – Change the electron energy only within a tiny slice 2 – Use dispersive element to separate the slice from the core 3 – Use a slit to select the slice and block the core beam Femto-slicing concept

9. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 9 I. General layout

10. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 10 C06 C07 C08 C09 C10 C05 C03 C04 C02 C01 Linac (100 MeV) Booster Storage ring (2.75 GeV) I. General layout

11. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 11 One single laser: CRISTAL beamline laser (5 mJ @ 1 kHz, 30 fs-fwhm, 800 nm) Modulator Wiggler CRISTAL (U20) TEMPO (HU44 + HU80) Medium Section Short Section Medium Section Laser Beam DEIMOS (HU52 + HU65) Medium Section Short Section GALAXIES (U20) I. General layout

12. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 12 Modulator: a wiggler used for femto-slicing and as a source for PUMA beamline Modulator Wiggler CRISTAL (U20) TEMPO (HU44 + HU80) Medium Section Short Section Medium Section Laser Beam DEIMOS (HU52 + HU65) Medium Section Short Section GALAXIES (U20) I. General layout

13. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 13 Wiggler TypeHybrid out-vacuum Magnetic period164.4 mm Period number20 Magnetic gap14.5 mm – 240 mm Magnetic componentsPoles: VACOFLUX50 (Saturation field: 2.35 T) Magnets: VACODYM 764 TP (magnetization: 1.37T) Max. magnetic field1.81 T Modulator: a wiggler used for femto-slicing and as a source for PUMA beamline I. General layout

14. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 14 Modulator Wiggler CRISTAL (U20) TEMPO (HU44 + HU80) Medium Section Short Section Medium Section Laser Beam DEIMOS (HU52 + HU65) Medium Section Short Section GALAXIES (U20) dipole Slice separation using the machine’s horizontal dispersion function I. General layout

15. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 15 cor Modulator Wiggler SDC6 SDM8 Laser Beam SDM7 SDC7 SDM6 CRISTAL (U20) TEMPO (HU44 + HU80) DEIMOS (HU52 + HU65) GALAXIES (U20) Beamline entrance slit shifted Core 3 mm Additionnal chicane to reduce the photon emission angle Slice Effective Dispersion D eff (m) S (m) Slice separation using the machine’s horizontal dispersion function I. General layout

16. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 16 Modulator Wiggler CRISTAL (U20) TEMPO (HU44 + HU80) Medium Section Short Section Medium Section Laser Beam DEIMOS (HU52 + HU65) Medium Section Short Section GALAXIES (U20) 2 Phase 1 beamlines (CRISTAL, TEMPO) 1 beamline under study (DEIMOS) 2 extra possible beamlines ? (GALAXIES, SEXTANTS) Delivery to several beamlines: 75 fs 140 fs 80 fs 210 fs I. General layout

17. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 17 II. Laser transport

18. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 18 Laser transport: Over 80 m from hutch to interaction point 22 mirrors (4 under remote control…) ~150 m of beampipes 5 vacuum chambers for mirrors 6 imaging systems 0 : Wiggler DIAG_IR DIAG_101 DIAG_GX01 DIAG_103 ENC104 ENC105 DIAG_GX20 DIAG_GX02 ENC103 ENC102 ENC101 LASER Output AFO 01 ATT 01 MgF 2 DIAG_00 55 m LASER ROOM LENS101 PUMA BL AFO 01 ATT 01 MgF 2 STORAGE RING ROOF STORAGE RING TUNNEL CRISTAL BL EXPERIMENTAL HALL DIAG_001 Wiggler II. Laser transport

19. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 19 Laser transport: Focussing with a 9m lens 0 : Wiggler DIAG_IR DIAG_101 DIAG_GX01 DIAG_103 ENC104 ENC105 DIAG_GX20 DIAG_GX02 ENC103 ENC102 ENC101 LASER Output AFO 01 ATT 01 MgF 2 DIAG_00 55 m LASER ROOM LENS101 PUMA BL AFO 01 ATT 01 MgF 2 STORAGE RING ROOF STORAGE RING TUNNEL CRISTAL BL EXPERIMENTAL HALL DIAG_001 Wiggler II. Laser transport wiggler

20. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 20 Goal : Alignement of the laser on the electron beam – Temporally (synchronization) – Spatially – Spectrally (fundamental wiggler wavelength = laser wavelength) III. InfraRed diagnostics

21. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 21 0 : Wiggler DIAG_IR MIR 001 WIN 001 FGL 610 LEN 100 MIR 002 Wiggler  In Vacuum Cu Mirror  Saphhire Window  Filters  2.5 m Lens  R max Mirror 900 mm 300 mm STORAGE RING TUNNEL Laser + Synchrotron Radiation extraction: III. InfraRed diagnostics

22. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 22 0 : Wiggler DIAG_IR MIR 001 WIN 001 FGL 610 LEN 100 MIR 002 Spatial overlap: Optics + CCD for imaging in the wiggler  Basler Spectral overlap: Spectrometer  Ocean Optics USB2000 Temporal overlap: Fast photodiode  FPD 310-FV from Menlo Wiggler  In Vacuum Cu Mirror  Saphhire Window  Filters  2.5 m Lens  R max Mirror 900 mm 300 mm STORAGE RING TUNNEL IR detectors: III. InfraRed diagnostics

23. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 23 Wiggler entry 1 pixel on the CCD ≡ 20 µm in the transverse plane of the wiggler Wiggler middle Wiggler exit SR Laser III. InfraRed diagnostics Spatial alignment of the laser on the SR:

24. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 III. InfraRed diagnostics Synchronization of the laser on the e- beam: Measure arrival time of the SR on the photodiode Measure arrival time of the laser Adjust the laser delay to equal the SR’s Final resolution : +/- 10 ps 24 SR Laser 1 ns

25. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 III. InfraRed diagnostics Spectral overlap: No straight forward measurement (presence of filters on the IR diagnostics board) 25

26. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Experiment / Simulation MeasuredSimulated MeasuredSimulated

27. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 III. InfraRed diagnostics Spectral overlap: No straight forward measurement (presence of filters on the IR diagnostics board) Measure the laser spectrum in the laser hutch Define the central wavelength Adjust the wiggler gap to the resonant wavelength 27 Wiggler gap [mm] Lambda Res [nm] from magnetic measurements 14.5941.7 15902.07 15.5864.61 16829.86 16.3810.01 16.4803.60 16.5797.17 16.6790.9 16.7784.68 16.8778.51 17766.53 20618.73 Laser

28. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 28 IV. THz diagnostics Goal : Check that there is interaction Optimize the interaction

29. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 29 IV. THz diagnostics Principle : Interaction creates a hole

30. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 30 IV. THz diagnostics Principle : Interaction creates a hole Sub-mm hole (~ps) gives coherent THz radiation

31. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Wiggler Laser 31 -1 0 1 Time (ps) 1010 -1 0 1 Time (ps) 1010 IV. THz diagnostics Principle : Good interaction = “Big hole” “Big hole” = Big THz signal

32. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Wiggler Laser THz pulses extracted @ AILES beamline 32 -1 0 1 Time (ps) 1010 -1 0 1 Time (ps) 1010 IV. THz diagnostics Setup : High sensitivity measurements: Bolometer  IR Labs 1.7 µs, oscillo Lecroy 1GHz Fast measurements (turn by turn): THz diode  Virginia Diode Virginia 1 ns  ACST 1 ns

33. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 33 V. THz measurements Beginning of the commissioning: January 2014 First THz signal: September 2014…

34. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 ~ 60 mV ~ 600 mV 21/09/2015 V. THz measurements Bolometer typical signal :

35. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 ~ 60 mV ~ 600 mV 21/09/2015 V. THz measurements Diode typical signal :

36. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz intensity vs beam current

37. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 P_laser = 1.7 W ; DT=33 fs ; Tirage = 4.5 mm ; gap=16.7 mm THz intensity vs beam current  For I > 8 mA : microbunching instability ->> CSR bursts I = 8 mA (blue) I = 9 mA (red)

38. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 P_laser = 1.7 W ; DT=33 fs ; Tirage = 4.5 mm ; gap=16.7 mm  THz signal still « visible » up to 15 mA but << to CSR bursts I=15 mA THz intensity vs beam current

39. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 39 THz intensity vs wiggler gap

40. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 40 First results : THz intensity vs delay laser / e- Bolometer signal vs synchro. P laser = 0.230 W. Pulse laser duration = 25 fs-fwhm. Focussing = 12.5 mm. Wiggler gap = 16.7 mm. I=4 mA.

41. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Laser stays in its initial position Electron beam displaced parallel to the reference orbit using bumps Optimum at - 100 µm / Sensitivity : +/- 600 µm ! THz intensity vs e- beam position in SDM6 (H)

42. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Optimum at + 300 µm / Sensitivity : +/- 900 µm THz intensity vs e- beam position in SDM6 (V) Laser stays in its initial position Electron beam displaced parallel to the reference orbit using bumps

43. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz intensity vs MIR104 setting : MIR104 = mirror on the tunnel roof, just before the shielded box MIR104 = last motorized mirror on the transport ->> used for alignement Result : we loose the THz signal when displacing the laser spot on CAM.001 by : +/- 15 pixels in V +/- 30 pixels in H High sensitivity to the laser transport ! THz intensity vs laser transport

44. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz intensity vs laser power

45. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz intensity vs pulse duration Chirp < 0 Chirp > 0  Optimum THz @ 500 fs but very disymetric response vs chirp…

46. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Chirp < 0 Chirp > 0 First results : THz intensity vs pulse duration  Optimum THz @ 500 fs but symetric response vs chirp…

47. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz signal simulation  Optimum THz @ 500 fs but symetric response vs chirp… ????

48. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 P_laser = 1.7 W ; DT=33/500 fs ; Tirage = 4.5 mm ; gap=16.7 mm Basse résolution THz spectrum on AILES beamline

49. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 THz spectrum on AILES beamline P_laser = 1.7 W ; DT=33/500 fs ; Tirage = 4.5 mm ; gap=16.7 mm FT of the electron bunch longitudinal profile

50. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 Next steps : ->> Reproduce experiment with simulations ->> Observe fs pulses @ CRISTAL ->> Deliver to other beamlines Conclusion

51. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 51 Sources and Accelerators Division Head of the project (Accelerator part): A. Nadji Deputy : M.-E. Couprie Commissioning coordinators: M. Labat and M.-A. Tordeux Accelerator physics: M.-A. Tordeux, P. Brunelle, L. S. Nadolski, A. Loulergue Diagnostics: M. Labat, L. Cassinari, F. Dohou, D. Pedeau, J.-P. Ricaud Insertion Devices & Chicane: O. Marcouillé, T. El Ajjouri, H. Abualrobf, F. Marteau, J. Vétéran, M.-E. Couprie. Steering committee: M.-E. Couprie, J. Luning, P. Morin, A. Nadji, P. Prigent Technical Division Vacuum: C. Herbeaux, N. Béchu Mechanical Engineering: J.-L. Marlats, D. Zerbib, S. Génix, K. Tavakoli, A. Mary C. De Oliveira, C. Créoff, S. Bonnin Survey and Alignement: A. Lestrade, M. Ros Infrastructure: P. Eymard, P. Goy General Division Radiation safety: J.-B. Pruvost, M. Hafsi, F. Ribaud Laser Safety: L. Germain, J.P. Laurent Methods: H. Rozelot Experiences Division Head of the project (Experience part): J. Luning Deputy: P. Prigent Commissioning coordinators: P. Hollander, CRISTAL, TEMPO Instrumentation & Coordination: P. Hollander, P. Prigent Detectors : S. Hustache Optics: F. Polack, T. Moreno CRISTAL Beamline: C. Laulhé, S. Ravy TEMPO Beamline: M. Silly, F. Sirotti Informatics Division (ECA)S. Zhang, J. Bisou, Y.M. Abiven (ISI)E. Moge, P. Gattoni (ISG)J. Guyot (ICA)O. Roux, S. Le Femto-slicing project team

52. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 52 ParameterUnitValue EnergyGeV 2.739 Revolution periodµs 1.18 Nb of bunches (max)- 416 Energy spread- 0.00125 Longitudinal Damping time Transverse Damping timems 3.47 6.93 Horizontal emittancenm.rad 3.9 Controlled Coupling% 1 Bunch lengthps-rms 25 @ 5 mA Beam life timeh 12h @ 430 mA SOLEIL main parameters: Femto-slicing @ SOLEIL: Setup

53. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 53 Femto-slicing@ SOLEIL main parameters: ParameterUnitValue Laser wavelengthnm 800 Laser pulse energymJ 5 @ 1 kHz Laser pulse durationfs-fwhm 30 – 1000 Laser quality (M²)- < 1.5 Laser Rayleigh lengthm 0.6 – 0.7 Laser repetition ratekHz 1 Wiggler periodmm 164.4 Resonant wavelength nm ~ 785 Current / bunchmA 10 Filling pattern- 1-8 bunches, exotic hybrid Femto-slicing @ SOLEIL: parameters

54. M. Labat, Femtoslicing @ SOLEIL Journées Accélérateurs, Roscoff, Octobre 2015 54 THz intensity vs laser focussing Bolometer signal vs laser focussing. P laser = 0.230 W. Pulse laser duration = 25 fs-fwhm. Gap wiggler = 16.7 mm. I < 4 mA.