CALCULATIONS OF THE LCLS INJECTOR USING ASTRA

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CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
Jean-Paul Carneiro DESY Hamburg ICFA Future
Light Sources Sub-PanelMini Workshop on
Start-to-End Simulations of X-RAY FELs DESY
Zeuthen, 18 August 2003
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LCLS ACCELERATOR SCHEMATIC
RF GUN
L01
Linac-X L 0.6 m
L02
Undulator L 120 m
Linac-1 L 9 m
Linac-2 L 330 m
Linac-3 L 550 m
35 Deg
existing linac
BC 1
BC 2
From LCLS Conceptual Design Report
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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LCLS INJECTOR
SOLENOID
RF GUN SOLENOID
L01
L02
9.4 M
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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RF GUN (SUPERFISH SIMULATIONS)
4.2 cm
15 cm
RF GUN PARAMETERS
1.6 cells, p-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 gt
at 263 nm
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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SOLENOIDS (POISSON SIMULATIONS)
Emittance compensating solenoid max Bz
0.27235 T at 18.9 cm L01 solenoid max Bz
0.748 T
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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ASTRA
For PARMELA / ASTRA comparisons 30 000
particles For ELEGANT input 200 000
particles, 12 digits Space charge calculation
N_rad 20, N_long60 ? N_rad 60 µm,
N_long50 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.
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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LCLS LASER (ASTRA GENERATOR OUTPUTS, 2E5 p.)
Transverse distribution uniform, r 1.2 mm
Longitudinal distribution uniform, L10 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 distribution
Transverse distribution
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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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
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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LONG. PHASE SPACE AT GUN EXIT (15 CM)
Phase laser in ASTRA (and PARMELA) 32 Deg
ASTRA GUN FIELD 120 MV/m
ASTRA GUN FIELD 120.15 MV/m
HEAD
HEAD
TAIL
TAIL
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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GUN EXIT (15 CM)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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GUN EXIT (15 CM)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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GUN EXIT (15 CM)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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GUN EXIT (15 CM)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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GUN EXIT (15 CM) RESUME
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
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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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
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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ENERGY GAIN ALONG LCLS INJECTOR
PARMELA 149.96 MeV/c ASTRA 149.14
MeV/c (0.5 )
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EXIT L01(4.46 M)
Long. Phase Space for 3 phases of L01
Phase ASTRA L01 at 5.5 Deg
HEAD
HEAD
MAX FIELD L01 24.0 MV/m
MAX FIELD L01 24.025 MV/m
TAIL
TAIL
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EXIT L01(4.46 M)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EXIT L02 (8.42 M)
Long. Phase Space for 3 phases of L01
Phase ASTRA L01 at -2.5 Deg
MAX FIELD L02 40.66 MV/m
MAX FIELD L02 40.68 MV/m
HEAD
HEAD
TAIL
TAIL
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EXIT L02 (8.42 M)
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EMITTANCE SIZE ALONG LCLS INJECTOR
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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ENERGY SPREAD BUNCH LENGTH ALONG LCLS INJECTOR
Jean-Paul Carneiro
CALCULATIONS OF THE LCLS INJECTOR USING ASTRA
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EXIT L01 (4.46 M) RESUME
(0.22)
(4)
(0.35)
(7)
(10)
(7)
(3)
Jean-Paul Carneiro
ASTRA SIMULATIONS OF THE LCLS INJECTOR
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EXIT L02 (8.42 M) RESUME
(0.5 )
(6)
(10)
(2 )
(10)
(2 )
(2)
Jean-Paul Carneiro
ASTRA SIMULATIONS OF THE LCLS INJECTOR
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DISTRIBUTION AT 9.4 M ( FOR ELEGANT)
Comparison ASTRA output at 9.4 m with elegant
input of S2E workshop
HEAD
TAIL
HEAD
TAIL
Jean-Paul Carneiro
ASTRA SIMULATIONS OF THE LCLS INJECTOR
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DISTRIBUTION AT 9.4 M ( FOR ELEGANT)
HEAD
HEAD
TAIL
TAIL
Jean-Paul Carneiro
ASTRA SIMULATIONS OF THE LCLS INJECTOR
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CONCLUSION
GOOD AGREMENT BETWEEN ASTRA AND PARMELA FOR THE
LCLS INJECTOR JITTER STUDIES NEED TO BE DONE
Jean-Paul Carneiro
ASTRA SIMULATIONS OF THE LCLS INJECTOR