Design consideration of the RF deflector to optimize the photo injector at PITZ
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P I T Z Photo Injector Test Facility Zeuthen Design consideration of the RF deflector to optimize the photo injector at PITZ S.Korepanov
description
Design consideration of the RF deflector to optimize the photo injector at PITZ. S.Korepanov. The prospect diagnostic complex for the beam phase analysis. Longitudinal resolution length in the tomography module: At the Screen4 ~ 0.15 mm (0.5 ps) – 55 slices - PowerPoint PPT Presentation
Transcript of Design consideration of the RF deflector to optimize the photo injector at PITZ
P I T ZPhoto Injector Test
Facility Zeuthen
Design consideration of the RF deflector to optimize the photo injector at PITZ
S.Korepanov
P I T ZPhoto Injector Test
Facility Zeuthen
Q Q Q Q Q Q Q Q Q Q Q
K K K K
Screen1
DC
Screen2 Screen3 Screen4
~ 6 m
matching
tomography module
Dispersive arm
Screen
The prospect diagnostic complex for the beam phase analysis
Longitudinal resolution length in the tomography module:At the Screen4 ~ 0.15 mm (0.5 ps) – 55 slicesAt the Screen1 ~ 0.35 mm (1.1 ps) – 23 slices
Vertical screen size ~ 30 mm
P I T ZPhoto Injector Test
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RF
Deflection
Classic cavity “Paramonov” cavity
Travelling wave cavity“LOLA”
Length ~ 0.7 mf = 1.3 GHz
a) D.Alesini, C.Vaccarezza, “Longitudinal and transverse phase space characterization”, SPARC-RF-03/003, INFN/LNF, Frascati, 2003
b) V.Paramonov, et. al. “Effrctive standing-wave RF structure for charged-particle deflector”, LINAC, 2006
c) O.H.Altenmueller, et.al., “Investigations of traveling – wave separator s for the Stanford two-mile linear accelerator”, The rev. of Sci. instr., Vol.35(4), 1964
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c)
P I T ZPhoto Injector Test
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3.185 3.19 3.195 3.2 3.205 3.21 3.215 3.22
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Pz, eV/c3.185 3.19 3.195 3.2 3.205 3.21 3.215 3.22
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3.185 3.19 3.195 3.2 3.205 3.21 3.215 3.22
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Pz, eV/cPz, eV/c
Pz, eV/c
Red line – initial distributionBlue line – distribution after:• Classic cavity• “Paramonov” cavity• Traveling wave cavity (LOLA)
Maximum resolution ~ 25 keV/c (~10-3)
<Pz> 32 MeV/c
P I T ZPhoto Injector Test
Facility ZeuthenResults of the simulations:
• For the all kind of the cavities the beam emittance has changed from 0.96 mm mrad to ~1.02 mm mrad• Steady wave cavity requires less RF power. • Travelling wave cavity has small field filling time. => Possibility to analyze a single bunch in the train.
Classic cavity “Paramonov” cavity Travelling wave cavity
Tomography Dispersive Tomography Dispersive Tomography Dispersive
Distance, m 2-4.2 6 2-4.2 6 2-4.2 6
V, MV 0.85-1.8 0.6 0.85-1.8 0.6 0.85-1.8 0.6
Q 21000 21000 15000 15000 19000 19000
PRF, MW up to 1 0.12 up to 0.17 0.02 up to 9.1 1.01
Field build up, s
~20 ~20 ~20 ~20 ~0.2 ~0.2
P I T ZPhoto Injector Test
Facility ZeuthenSummary:
• The three different deflector were analyzed in complex with the tomography module and the dispersive section.• The longitudinal resolution length for the beam analysis in the tomography module is 0.35mm (0.5 ps).• Resolution of the dispersive section is limited by 25 keV• Transverse emittance distortion by the deflector and the kicker is about a few %.
To do:• Try to reduce the longitudinal momentum distortion in the deflector (D.Alesini).• More detail cavity analysis. Design the real geometry (coupler, load). (D.Alesini)
P I T ZPhoto Injector Test
Facility Zeuthen
Q Q Q Q Q Q Q Q Q Q Q
K K K K
Screen1
DC
Screen2 Screen3 Screen4
~ 6 m
matching
tomography module
Dispersive arm
Screen
The prospect diagnostic complex for the beam phase analysis
Longitudinal resolution length in the tomography module:At the Screen4 ~ 0.15 mm (0.5 ps) – 55 slicesAt the Screen1 ~ 0.35 mm (1.1 ps) – 23 slices
P I T ZPhoto Injector Test
Facility ZeuthenKicker (TESLA damping ring kicker)
• Free aperture 50mm x 50 mm• Length 300 mm• Field rise/fall (10%-90%) ~5 ns• Pulse length 30 ns• Repetition rate 2 MHz (~100 pulses), 5 Hz• Deflection for 30 MeV up to 6.6 mrad
Frank Obier (DESY -MIN-)
For PITZ2 beam:L =1m – distance between kicker and the screen
Deflection angle ~2 mradOff axis ~ 2 mm
Pz ~ 1% Pz=> xrms ~ 10 m
Xrms ~ 120 m
P I T ZPhoto Injector Test
Facility ZeuthenFlange fields effect (estimation)
beam
By(x=0,y,z)
The beam is deflected by By.
Inhomogeneity ~ 0.4%
P I T ZPhoto Injector Test
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The gap in the initial distribution - 0.15 mm
Red line – initial distributionBlue line – distribution after:• Classic cavity• “Paramonov” cavity• Traveling wave cavity (LOLA)
P I T ZPhoto Injector Test
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Diagnostic complex for beam phase space analysis
Longitudinal slice transverse emittance measurements
DC + Tomography module
Longitudinal phase space analysis
DC + Dispersive arm
Q Q Q Q Q Q Q Q Q Q Q
Screen1
DC
Screen2 Screen3 Screen4
~ 6 m
matching
tomography module
Dispersive arm
Screen
7.5 m
D.J.Holder, et. al., “A phase space tomography diagnostic for PITZ”, EPAC2006, Edinburgh, UK
P I T ZPhoto Injector Test
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average long. momentum 32 MeV/c
min. norm. emittance (rms) ~ 1 mm mrad
transverse beam size on the screen in the tomography module, rms (full)
~ 0.12 (0.7) mm
full longitudinal beam size 8 mm (27 ps)
pulse frequency 1-9 MHz
repetition rate 10 Hz
Beam parameters for the simulations:
