Bunch Compressor 3

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Bunch Compressor 3

• Torsten Limberg for Frank Stulle et al.

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Basic Bunch Compression Mechanism with Magnetic
Chicane
Ds -R56d
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TTF-II Compression System
Two stage compression to avoid space charge
emittance dilution on one hand and reduce
non-linear effects from the RF system on the
other.
BC2
BC3
BC2
BC3
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BC-3 Lay Out
R56 0.025 - 0.1 mm
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Incoming optics matching section
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First half of S-bend
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2nd part of S-bend
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Outgoing matching section
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Horizontal Dispersion in BC-3
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Optics of BC-3
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Longitudinal Phase Space Evolution
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TraFiC4 results slice emittance and projected
emittance development through BC-3 for different
designs
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Transverse emittance, peak current, mean energy
of longitudinal slices and energy spread along
the bunch at the undulator entrance (ca. 60 of
the bunch saturates _at_ l6nm)(s gt 0 corresponds
to the bunch tail)
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TTF-II Starting Scenario (l30nm)
BC2
BC2
BC3
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Transverse emittance, current, energy spread
along the bunch and longitudinal phase space at
entry of BC-2(E. Schneidmiller et al.)
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Transverse emittance, current, energy spread
along the bunch and longitudinal phase space at
exit of BC-2
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Transverse emittance, current, energy spread
along the bunch and longitudinal phase space at
exit of BC-3 (including CSR effects in 1-d model)
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Transverse emittance, current, energy spread
along the bunch and longitudinal phase space at
entry of undulator (including space charge
effects in upstream drift)
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Peak current vs. transverse emittance for given
slice energy spread and saturation at the end of
the undulator (l30nm, 30 safety)
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Status of Instrumentation (D. Nölle)

• Strip lines (4) April 03
• Pickup Array (2) feed throughs
  ready for assembly
• Toroids (2) March 03
• OTR Stations Standard (2) Feb 03
• OTR Special _at_ 75 m OTR System OK,
  chamber not ordered
• _at_ 78 m design done, window
  flanges, screen and optical system need to be
  procured
• Resistance Monitor April 03
• Phase monitor March 03

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Vacuum Chamber Support Status
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Summary

• BC3 design complete and fabrication of components
  mostly on schedule
• Two operating scenarios for the bunch compression
  system
• With 3rd harmonic RF
• Full start to endsimulation done, lases at 6 nm
• For start up No 3rd harmonic RF, lower energy
• Start to end simulation begun, lases at 30 nm