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Perspectives of Plasma-Wakefield Acceleration
• basics• perspectives• state-of-the-art• brief overview of various projects
F. Grüner, Universität Hamburg & Center for Free-Electron Laser Science
basic principle of any accelerator
one needs an electric field…
charge separation
+ -
electron
-
…charged particles are then accelerated
plasma cell:cm short!!!!....
but also quite small…
lab setup of a Laser-Plasma-Accelerator at MPQ (S. Karsch et al.) pulse of a high-Power laser
plasma wakefield acceleration
high-intensitylaser:~ 5 J / 25 fs
plasma(capillary)
laser pulse withrelativistic intensity
typical length scale = plasma wavelength
wake
plasma
Ez ~ TV/m
~ 5 fs
PIC simulation (M. Geissler)
• EuroNNAc workshop @ CERN, May 2011, top 5 goals, among them
- „table-top“ XFEL- 10 GeV stage- stable operation 24/7
• brilliant X-ray sources „at home“, added values:
- intrinsic synchronization (driver laser, X-ray pulse, few fs)- compact enough for hospitals: medical applications- higher peak currents (above 20 pC/4 fs)
• high-energy physics
- TeV machine- sure enough, many open questions (emittance growth, staging,
timing/pointing for ~100 stages, efficiency,…..)
perspectives
Leemans & Esarey, Physics Today, March 2009
~ 16 m
• before 2000: theory on LWFA, experiments with „thermal“ energy spectra
• 2000 theory of bubble acceleration (Meyer-ter-Vehn & Pukhov, MPQ): needs stronger laser
• 2004 first experimental results, peaked energy spectra (LBNL, LOA, RAL, Nature)
• 2006 Berkeley lab reaches 1.0 GeV (W. Leemans et al., Nature Physics)
• 2008 stability improvement (e.g., J. Osterhoff et al., PRL)
• 2009 first laser-driven soft X-ray undulator source (F. Grüner et al., Nature Physics)
• 2010-… diagnostics: bunch length, emittance, position behind laser new injection schemes: down-ramp, counter-propagating lasers, ionization, shock-front
state of the art
courtesy of S. Karsch
open questions how does it all work?
• key questions- emittance growth- energy spread- injection- beam loading- exit into vacuum- staging scalable?
• selft-consistent analytical treatments too complex → PIC codes
• but: PIC codes suffer from- idealistic modelling- numerical heating- resolution issues (space charge)
PWA worldwide
LOALOA
Imperial CollegeRutherford Lab
StrathclydeOxford
Imperial CollegeRutherford Lab
StrathclydeOxford
DüsseldorfJena
DresdenMunich
Hamburg
DüsseldorfJena
DresdenMunich
Hamburg
JAEA, NaraJAEA, Nara
APRIAPRI
LundLund
BerkeleyLincoln
Ann ArborAustin
Livermore
BerkeleyLincoln
Ann ArborAustin
Livermore
BejingShanghai
…
BejingShanghai
…
FrascatiFrascati
research clusters in Germany
name start run time partners
TransRegio 18 2004 3 x 4 years Düsseldorf,Jena, LMU, MPQ, MBI
MAP Cluster of Excellence
2006 5+1 years follow-up proposal 2011
LMU, MPQ, TUM
Helmholtz Association: ARD
2011 2011-2015, then PoF3 HZDR, DESY, HI Jena, UHH, CFEL
CALA 2011 new university institutebuilding ready, start 2013
LMU, TUMLMU,
MPQ
MBI
Düssel-
dorfJena
HZDR
DESY, UHH/CFEL
Düsseldorf(Oswald Willi et al.)
Düssel-
dorf
lasers 10 TW + 100 TW + 200 TW (25 fs)all synchronized
planned upgrades: 100 → 200 TW; XPW (1012
contrast)
current electron beams
gas jets: 330 MeVgas targets (5-15 mm): stable 110 MeV
research testing microchips for outer spacestaging of plasma acceleratorstheory + simulations
Jena(Malte Kaluza et al.)
lasers JETI: 32 TW (25 fs) on target, plasma mirrors for >1012 contrast
planned upgrade: 2012 2.5 J
current electron beams
300 MeVenergy spread 1-2 %charge 1-15 pC
research light sources (THz, betatron, undulator)cell irradiatione-beam diagnostics (with MPQ)
highlight direct observation of electrons inside bubble
Jena
M. Kaluza et al., PRL 2010
A. Buck et al., Nature Phys. (2011)
Max-Born Insitute (Berlin)(Matthias Schnürer et al.)
lasers 100 TW (25 fs) coupled with 30 TW (45 fs)
current electron beams
so far ion accelerationelectrons start in 2012
research (plasma) pump (ion/photon) probe experimentsstaging of plasma accelerators
highlight record efficiency for laser into ion energy
MBI
HZDR (Dresden)(Ulrich Schramm et al.)
HZDR
lasers 150 TW (25-30 fs)
upgrade: 500 TW (25-30 fs), 2012 1 PW end of 2013
current electron beams
so far ion accelerationelectron acceleration started; joint experiments with DESY/UHH
research injection of external ELBE beam (100 fs)
LMU/MPQ (Munich)(S. Karsch, L. Veisz, F. Grüner, et al.)
lasers ATLAS: 100 TW (25 fs, Ti:Sapph)LWS-20: 16 TW (8 fs, OPCPA)
planned upgrades: LWS-100 (5 fs)ATLAS-3000, PFS: 5J/5fs/1kHz (in CALA)
current electron beams
LWS-20: 20-40 MeV, 5-6 fs (measured)ATLAS: >500 MeV, >100 pC
research e-beam diagnostics (bunch length, emittance)light sources (undulator, table-top FEL design, medical imaging)theory + simulation
highlight highly stable 200-600 MeV electronsfirst laser-driven soft X-ray undulator source
LMU,MPQ
M. Fuchs,…, J. Osterhoff, …,S. Karsch, F. Grüner, Nature Phys. 5, 826 (2009)
LAOLA = DESY+UHH+CFEL(laola.desy.de)
DESY, UHH, CFEL
laser March 2013: 200 TW (5J / 25 fs)
planned projects
combining modern accelerators with PWA:
• beam-driven self-modulation (PITZ)• transformer ratio studies (PITZ+FLASH)• external injection (REGAE+FLASH)
cooperations • ARD (Dresden+Jena)• MAP• SLAC + Berkeley• MBI• MPP• JAI