CIEMAT ACTIVITIES ON STRIPLINE KICKERS

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CIEMAT ACTIVITIES ON STRIPLINE KICKERS
I. Rodríguez
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Outline

• CTF3 Combiner Ring Kicker
• CTF3 TL2 Tail Clippers
• Stripline kickers in ILC
• Conclusions

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CTF3 Combiner Ring Kicker (1)

• Kicker location in CTF3 Combiner Ring (CR)

KICKER

• Extraction of beam after 4-turns combination in
  the CR
• Substitution of an old magnetic kicker to improve
  beam impedance

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CTF3 Combiner Ring Kicker (2)

• Specifications to meet

• 1 homogeneity is the most challenging
  specification

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CTF3 Combiner Ring Kicker (3)

• Design and calculations
• Several cross sections considered. Planar
  electrodes chosen
• 3D model in HFSS 1.7 m electrodes.
• Good transmission of pulse frequency content
• Wakefields studied using CST Particle Studio at
  CIEMAT and GDFidl at CERN

• Aperture 41 mm
• Electrode height 44 mm
• Tube radius 54 mm
• Border angle  42º
• Border length  8.2 mm
• Electrode width  2 mm
• Z0 49.99 O
• Homogeneity 0.74

S112lt0.03 (0 to 50 MHz)
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CTF3 Combiner Ring Kicker (4)

• Manufacturing Fully in stainless-steel
• Many high vacuum welds required
• Challenging stand-off support
• Special beam pipe transitions

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CTF3 Combiner Ring Kicker (5)

• Testing
• Vacuum test and leak rate successful. Mild bake
  out required
• High voltage pulser test 16 kV, 5 ns, 50 Ohm
  load
• DC high voltage test 18 kV successfully tested
  (14 kV nominal)
• RF tests

Almost no reflection lt 0.2 in power up to 35
MHz
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CTF3 TL2 Tail Clippers (1)

• Tail Clippers location in CTF3

TAIL CLIPPERS

• Shorten the bunch trains for conditioning before
  PETS
• Extremely fast response required to precisely cut
  the beam between bunches

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CTF3 TL2 Tail Clippers (2)

• Specifications to meet

• High frequency transmission is the most
  challenging specification

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CTF3 TL2 Tail Clippers (3)

• Design and calculations
• Several cross sections considered
• Smooth coax to stripline transitions for enhanced
  RF transmission
• Excellent high frequency transmission up to 2 GHz

Homog19Ø 66 mm
Homog15Ø 71 mm
Homog10Ø 78 mm
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CTF3 TL2 Tail Clippers (4)

• Manufacturing
• Stainless steel tube and aluminium electrodes
• Electrodes fully manufactured using CNC
• High voltage 50 Ohm feedthroughs
• Challenging coax to stripline connections

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CTF3 TL2 Tail Clippers (5)

• Testing
• Excellent leak test. Good vacuum. Mild bake-out
  required
• High voltage pulser test. Excellent behaviour at
  high freqs
• DC high voltage test 3 kV successfully tested (2
  kV nominal)
• RF tests

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ILC stripline kickers

• Many stripline kickers in different zones DRs,
  RTML, etc
• Most challenging ones Damping Ring injection and
  extraction kickers. DRs 6.7 km, 5 GeV.
• The electrical pulser requirements are extremely
  challenging.

ILC Reference Design Report (August, 2007)
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Conclusions

• Two stripline kickers have been fully designed,
  manufactured and tested. Tail Clipper power
  supplies were designed at CERN.
• ILC kickers are very similar except from the
  pulsed power supply.

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