1. CALCULATIONS OF THE LCLS INJECTOR USING ASTRA Jean-Paul Carneiro DESY Hamburg ICFA Future Light Sources Sub-Panel Mini Workshop on Start-to-End Simulations of X-RAY FELs DESY Zeuthen, 18 August 2003

2. LCLS ACCELERATOR SCHEMATIC Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA …existing linac Linac-1 L = 9 m Linac-2 L = 330 m Linac-3 L = 550 m Linac-X L = 0.6 m BC 1 BC 2 Undulator L = 120 m From LCLS Conceptual Design Report RF GUN L01 L02 35 Deg

3. LCLS INJECTOR Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA

4. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA RF GUN (SUPERFISH SIMULATIONS) 15 cm 4.2 cm RF GUN PARAMETERS 1.6 cells, π-mode, 2856 MHz 120 MV/m, ~ 9 MW 120 Hz, ~ 3 µs symmetric RF gun, 1 µm at 1.0 nC CATHODE Cu (possibly Mg) 12 mm usable diameter, QE > at 263 nm

5. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA SOLENOIDS (POISSON SIMULATIONS) Emittance compensating solenoid : max Bz = 0.27235 T at 18.9 cm L01 solenoid : max Bz = 0.748 T

6. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA ASTRA For PARMELA / ASTRA comparisons : 30 000 particles For ELEGANT input : 200 000 particles, 12 digits Space charge calculation : N_rad = 20, N_long=60  N_rad = 60 µm, N_long=50 µm, automatic adjustment of the mesh with the bunch. Increment step : min = 0.1 ps and max = 5 ps. Automatic adjustment of the increment step.

7. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA LCLS LASER (ASTRA GENERATOR OUTPUTS, 2E5 p.) Transverse distribution : uniform, r = 1.2 mm Longitudinal distribution : uniform, L=10 ps with 0.7 ps rise times Thermal emittance : 0.6 mm-mrad per mm radius (Cu cathodes) From TELSA-FEL 97-01 (K. Floettmann) : Longitudinal distributionTransverse distribution

8. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA PHASE SCAN OF LCLS AND TESLA XFEL WITH ASTRA LCLS: 120 MV/m, 0.27235 T, L= 10 ps + 0.7 ps rise time, r = 1.2 mm TESLA XFEL : 40 MV/m, 0.163 T, L = 20 ps + 3 ps rise time, r =1.5 mm

9. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA LONG. PHASE SPACE AT GUN EXIT (15 CM) Phase laser in ASTRA (and PARMELA) : + 32 Deg HEAD TAIL HEAD TAIL ASTRA GUN FIELD = 120 MV/mASTRA GUN FIELD = 120.15 MV/m

10. GUN EXIT (15 CM) Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA

11. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA GUN EXIT (15 CM)

12. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA GUN EXIT (15 CM)

13. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA GUN EXIT (15 CM)

14. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA GUN EXIT (15 CM) – RESUME UNITSASTRAPARMELA MOMEMTUM[MeV/c]6.14086.15 RMS ENERGY SPREAD[%]0.430.37 RMS SIZE X or Y[mm]1.691.78 RMS NORM. EMIT X or Y[mm-mrad]2.492.97 RMS BUNCH LENGTH[mm]0.800.78 PARMELA and ASTRA with 30 000 particles PARMELA & ASTRA : 120 MV/m, 0.27235 T, L =10 ps + 0.7 ps rise time, r =1.2 mm 0.15% 14% 5% 16% 2%

15. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA ACCELERATING SECTIONS L01 & L02 L01 & L02 : 3 m S-Band sections, 84 cells per section, TWS L01 located at 1.4 m and L02 at 5.4 m (from photo-cathode) PARMELA : uses TRWAVE for L01 & L02, with product of the average axial electric field in MV/m and the transit-time time factor T. For L01 : and for L02: ASTRA : uses the maximum field of the TW Emax From SUPERFISH : Superfish simulation of one TW cell

16. ENERGY GAIN ALONG LCLS INJECTOR Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA PARMELA : 149.96 MeV/c ASTRA : 149.14 MeV/c (0.5 %)

17. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA EXIT L01(4.46 M) HEAD TAIL HEAD TAIL MAX FIELD L01 = 24.0 MV/m MAX FIELD L01= 24.025 MV/m Long. Phase Space for 3 phases of L01 Phase ASTRA L01 at +5.5 Deg

18. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA EXIT L01(4.46 M)

19. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA EXIT L02 (8.42 M) HEAD TAIL MAX FIELD L02 = 40.66 MV/mMAX FIELD L02 = 40.68 MV/m Long. Phase Space for 3 phases of L01 Phase ASTRA L01 at -2.5 Deg

20. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA EXIT L02 (8.42 M)

21. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA EMITTANCE & SIZE ALONG LCLS INJECTOR

22. Jean-Paul CarneiroCALCULATIONS OF THE LCLS INJECTOR USING ASTRA ENERGY SPREAD & BUNCH LENGTH ALONG LCLS INJECTOR

23. Jean-Paul CarneiroASTRA SIMULATIONS OF THE LCLS INJECTOR EXIT L01 (4.46 M) – RESUME UNITSASTRAPARMELA MOMEMTUM[MeV/c]59.2859.41 RMS ENERGY SPREAD[%]0.680.65 RMS SIZE X[mm]0.320.35 RMS NORM. EMIT X[mm-mrad]1.010.94 RMS SIZE Y[mm]0.320.35 RMS NORM. EMIT Y[mm-mrad]1.010.94 RMS BUNCH LENGTH[mm]0.900.87 (0.22%) (4%) (0.35%) (7%) (10%) (7%) (3%)

24. Jean-Paul CarneiroASTRA SIMULATIONS OF THE LCLS INJECTOR EXIT L02 (8.42 M) – RESUME UNITSASTRAPARMELA MOMEMTUM[MeV/c]149.14149.96 RMS ENERGY SPREAD[%]0.180.17 RMS SIZE X[mm]0.320.29 RMS NORM. EMIT X[mm-mrad]0.980.96 RMS SIZE Y[mm]0.320.29 RMS NORM. EMIT Y[mm-mrad]0.980.96 RMS BUNCH LENGTH[mm]0.900.88 (0.5 %) (6%) (10%) (2 %) (10%) (2 %)

25. Jean-Paul CarneiroASTRA SIMULATIONS OF THE LCLS INJECTOR DISTRIBUTION AT 9.4 M ( FOR ELEGANT) Comparison ASTRA output at 9.4 m with elegant input of S2E workshop … HEAD TAIL HEADTAIL

26. Jean-Paul CarneiroASTRA SIMULATIONS OF THE LCLS INJECTOR DISTRIBUTION AT 9.4 M ( FOR ELEGANT) HEAD TAIL HEAD TAIL

27. Jean-Paul CarneiroASTRA SIMULATIONS OF THE LCLS INJECTOR CONCLUSION GOOD AGREMENT BETWEEN ASTRA AND PARMELA FOR THE LCLS INJECTOR JITTER STUDIES NEED TO BE DONE