Final Focus Test at ATF

1
Final Focus Test at ATF

• Shigeru KURODA

2
Goal

• Test of the Local ? Correction Optics
• Experience of Construction Tuning FF system
• Beam Stabilization to nm level using nanoBPM

3
Merit

• High quality ATF DR beam is available.
• E1.54 GeV
• ??x310-6 m
• ??x???y1001
• ?0.1 Gaussian Beam

4
Optics Geometry

• ?x10mm
• ? y0.1mm Similar to LC FF
• Lengths36.6 m construction in the hall is
  possible

5
Performance

• Tracking with 1000 particles
• ?x1e-9 m, ?y1e-11 m ?0.1 _at_entrance
• ?? x 3.76?m ? y 35.9nm _at_IP

6
Local ??Correction

• Same order of ? cancelled locally

7
Vibration Tolerance
7E-6
100nm
2nm
The above values are calculated for 10 beam
size growth/displacement of 10 beam size
Similar difficulty to stabilize the beam ?
8
Alignment Tolerance
CorrectionCorrection1 5x Correction2

• Correction1
• 3x(Orbit distortion corr.)
• Final Q mover dz ( 50 ?m step )
• SX mover dx dy ( 10 ?m step )
• Correction2
• 3x(Orbitdispersion distortion Corr.)
• Final Q mover dz ( 50 ?m step )
• SX mover dx dy ( 10 ?m step )

Errors for Simulation
The alignment tolerance is achievable
9
Summary

• ATF2 can be a good test facility for the LC FF.
• Test for the Local x Correction Optics
• Study of beam stabilization and correction
• Beam jitter control in nm level using nanoBPM
• Experience of fine alignment and FF beam
  operation
• Beam background study

• Optimistic option
• Having fast kicker
• --gt TESLA like beam at ATF
• ---gt Study of feedback system
• Study of Laser system for gg option