LOASIS Program:

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LOASIS Program All-optical accelerators Wim
Leemans LOASIS Program Accelerator and Fusion
Research Division
Website http//loasis.lbl.gov/
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Acknowledgment Staff/students of lOASIS
team E. Esarey, C.Filip, G. Fubiani, C.
Geddes, E. Michel, P. Michel, B. Nagler, K.
Nakamura, C. Schroeder, B. Shadwick, C. Toth, J.
van Tilborg, D. Syversrud, M. Dickinson, N.
Ybarrolazza, J. Wallig University of
Nevada, Reno Primary Collaborators S. Hooker, A.
Gonsalves- Oxford University D.
Jaroszynski-Strathclyde, AlphaX T. Cowan, N. Le
Galloudec, H. Ruhl, A. Kemp- UNR J. Cary, D.
Bruhwiler, D. Dimitrov-U Colorado Boulder,
TechX-Corp DOE -HEP Advanced Accelerator
Technology
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Challenges

• Building a high energy collider
• Single stage ?
• 200 m long plasma, BIG laser (200 PW for 1 TeV?)
• Will beam remain stable ? Will emittance be OK?
• Multi-stage ?
• How to stage ? Build 10 GeV module, how to
  couple beams in and out ?
• How to manage 100 - 1000, 0.1-1 PW systems? 100
  Hz?
• Radiation source
• Coherent emission THz
• X-FEL is beam quality good enough ?
• Energy spread
• Emittance
• Maintaining peak current bunch propagation
• Particle source
• fs, MeV electron bunches, pC, 10 micron spot,
  ?E/E ltlt

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Experimental activities/focus

• 10 TW system
• High density plasma channels
• Low phase velocity wakes
• Dark current free structure
• 100 MeV-class beams
• Injection physics
• THz and X-rays

• 100 TW system
• Low density plasma channels
• High phase velocity wakes
• 1 GeV module
• Capillary discharge
• Collab. With Oxford (UK)

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Next step 1 GeV compact module 100 TW laser
plasma channel
A. Reitsma et al., PR-STAB 2001

• Collaboration with Oxford University and Alpha-X

Bigger laser
2-7 cm long

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LWFAs brightness offers unique opportunities
Data Nature 2004
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Single drive beam experiments have been conducted
for laser accelerator produced THz and X-rays
Set-up for E-O effect

• THz emitted at vacuum-plasma boundary
• Short bunches result in coherent emission
• Radiation sourcebunch diagnostic
• Radiation characterized via
• Michelson interferometer
• Semiconductor switching
• Electro-optic effect in ZnTe

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Shot-to-shot stability in charge and bunch
duration enables scanning E-O sampling technique
Charge Stability over Time lt 5 rms

• Spectrum consistent with 50 fs bunch
• THz depends primarily on charge,
• bunch duration
• Shot-to-shot stability of those quantities

J. Van Tilborg et al., in preparation
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Ultra-short x-ray generation from laser
accelerated e-beams

• Betatron emission
• Spontaneously emitted
• Detector testing
• First phase of x-ray diagnostic
• Collaborations
• LLNL
• UNR

E. Esarey et al., PRE 2002 A. Rousse et al., PRL
2004
parameters Q03 nC E100 MeV rb3 mm ne2 x1019
cm-3 Lchannel1 mm
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LOASIS Program at LBNL

• Tools multi-beam, multi-arm laser
• Radiation shielded experimental areasremote
  control room
• Two target areas
• 10 TW (10 TW), 3 independent vacuum compressors
• 100 TW arm
• Physics
• Precision frontier all-optical injection
  enabled by discovery of dark current free
  structure
• High energy acceleration
• Channel guided laser wakefield 100 MeV (Nature
  2004)
• Capillary discharge injection towards 1 GeV
• Radiation sources taking advantage of peak
  brightness
• Intense THz via coherent transition radiation
  (PRL 2003, PRE 2004, PRL 2005(submitted))
• Incoherent x-rays betatron, Thomson
  scattering-gamma rays
• Coherent x-rays XFEL

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LOASIS Program FY05 Staff visitors and students