Advanced Accelerators for Future Particle Physics and Light Sources J. B. Rosenzweig UCLA Department of Physics and Astronomy AAAS Annual Meeting Chicago, February 13, 2009 J. B. Rosenzweig UCLA Department of Physics and Astronomy AAAS Annual Meeting Chicago, February 13, 2009

Introduction  Accelerators have been central tools in science for three-fourths of a century  Enables research both fundamental and essential  HEP colliders: structure of matter at basic level  Light sources: structure of matter at functional level  Modern accelerators have extreme sophistication  Performance optimized over decades  New ideas in context of mature technologies  Accelerator science is a victim of its own success  Demand for frontier capabilities met at …  Size and cost at limit of realizability, public support  Accelerators have been central tools in science for three-fourths of a century  Enables research both fundamental and essential  HEP colliders: structure of matter at basic level  Light sources: structure of matter at functional level  Modern accelerators have extreme sophistication  Performance optimized over decades  New ideas in context of mature technologies  Accelerator science is a victim of its own success  Demand for frontier capabilities met at …  Size and cost at limit of realizability, public support

AAAS 2009 Historical schematic of accelerators: Particle physics leads, spin-offs follow quickly Electrostatic Accelerators Betatron Cyclotron Ion Linear Accelerators Synchrotron Circular Collider Superconducting Circular Collider Electron Linear Accelerators Electron Linear Colliders Muon Collider? VLHC? Medicine Light sources (3 rd Generation) Nuclear physics X-ray FEL Laser/Plasma Accelerators? Ultra-High Energy LC? FFAG, etc.

Colliders and the energy frontier  Colliders uniquely explore energy (U) frontier  Exp’l growth in equivalent beam energy w/time  Livingston plot: “Moore’s Law” for accelerators  We have long been falling off plot  Challenge in energy, but not only…luminosity (high beam quality, density) as well  How to proceed?  Mature present techniques, or…  Discover new approaches  Colliders uniquely explore energy (U) frontier  Exp’l growth in equivalent beam energy w/time  Livingston plot: “Moore’s Law” for accelerators  We have long been falling off plot  Challenge in energy, but not only…luminosity (high beam quality, density) as well  How to proceed?  Mature present techniques, or…  Discover new approaches

Limitations on collider energy  Synchrotron radiation power loss  Forces future e + -e - colliders to be linear  Large(!) circular machines for heavier particles  Consider muons for lepton colliders?  Scaling in size/cost  Near unitary limits  Few 10 4 m in dimension  Few $/€ 10 9  Synchrotron radiation power loss  Forces future e + -e - colliders to be linear  Large(!) circular machines for heavier particles  Consider muons for lepton colliders?  Scaling in size/cost  Near unitary limits  Few 10 4 m in dimension  Few $/€ 10 9 Tevatron complex at FNAL (linacs, rings, buffalo…) 27 km circumference

The energy challenge  Avoid giantism  Cost above all  Higher fields give physics challenges  Circular machines: magnets  Linear machines: high field acceleration  Enter new world of high energy density physics  Beam density, energy  Beam quality must increase to compensate smaller cross-section  Stored field energy  Avoid giantism  Cost above all  Higher fields give physics challenges  Circular machines: magnets  Linear machines: high field acceleration  Enter new world of high energy density physics  Beam density, energy  Beam quality must increase to compensate smaller cross-section  Stored field energy High energy densty in action at the LHC

Linear accelerator schematic High energy density in future e- linear accelerators  High fields give violent accelerating systems  Relativistic e- oscillations  Diseases  Breakdown, dark current  Peak/stored energy  Power dissipation  Approaches  High frequency, normal cond.  Superconducting (many apps)  Laser-fed optical structures?  Laser = high peak power  Miniaturization…  High fields give violent accelerating systems  Relativistic e- oscillations  Diseases  Breakdown, dark current  Peak/stored energy  Power dissipation  Approaches  High frequency, normal cond.  Superconducting (many apps)  Laser-fed optical structures?  Laser = high peak power  Miniaturization… TESLA SC cavity

Approaches to new collider paradigms  Advancement of existing techniques  Higher field (SC) magnets (VLHC)  Use of more exotic colliding particles (muons)  Higher gradient RF cavities (X-band LC)  Superconducting RF cavities (TESLA LC)  Revolutionary new approaches (high gradient frontier)  New sources: i.e. lasers  New accelerating media: i.e. plasmas  Truly immersed in high energy density physics  Advancement of existing techniques  Higher field (SC) magnets (VLHC)  Use of more exotic colliding particles (muons)  Higher gradient RF cavities (X-band LC)  Superconducting RF cavities (TESLA LC)  Revolutionary new approaches (high gradient frontier)  New sources: i.e. lasers  New accelerating media: i.e. plasmas  Truly immersed in high energy density physics Cryostat with 16 T Nb 3 Sn magnet at LBNL Muon collider schematic (R. Johnson) Another Talk

HEP Spin-offf: X-ray SASE FEL based on SC RF linear accelerator  Synchrotron radiation is again converted from vice to virtue: SASE FEL  Coherent X-rays from multi-GeV e- beam  Unprecedented brightness  Cavities spin-off of TESLA program  Alslo high brightness e- beam physics  Beginning now  High average beam power than warm technologies (e.g. LCLS at Stanford)  Many SASE FEL projects worldwide  Synchrotron radiation is again converted from vice to virtue: SASE FEL  Coherent X-rays from multi-GeV e- beam  Unprecedented brightness  Cavities spin-off of TESLA program  Alslo high brightness e- beam physics  Beginning now  High average beam power than warm technologies (e.g. LCLS at Stanford)  Many SASE FEL projects worldwide 10 orders of magnitude beyond 3rd gen X-ray light source!

FNAL Colloquium The optical accelerator  Scale the linac from 1-10 cm to 1-10  m laser!  Scale beam sizes  Resonant linac-like structure  Slab symmetry  Take advantage of copious power  Allow high beam charge  Suppress wakefields  Limit on gradient?  1-2 GV/m, avalanche ionization  Experiments  ongoing at SLAC (1  m)  planned at UCLA (340  m) Resonant dielectric structure schematic Simulated field profile (OOPIC); half structure e-beam Laser power input

Inverse Cerenkov Acceleration  Coherent Cerenkov wakes can be extremely strong  Short beam, small aperture; miniaturization…  SLAC FFTB, N b =3E10,  z = 20  m, a =50  m, > 11 GV/m  Breakdown observed above 5.5 GV/m(!); on to plasma  Coherent Cerenkov wakes can be extremely strong  Short beam, small aperture; miniaturization…  SLAC FFTB, N b =3E10,  z = 20  m, a =50  m, > 11 GV/m  Breakdown observed above 5.5 GV/m(!); on to plasma Simulated GV/m Cerenkov wakes for typical FFTB parameters (OOPIC)

AAAS 2009 Past the breakdown limit: Plasma Accelerators  Very high energy density laser or e- beam excites plasma waves as it propagates  Extremely high fields possible:  Very high energy density laser or e- beam excites plasma waves as it propagates  Extremely high fields possible: Schematic of laser wakefield Accelerator (LWFA) Ex: tenous gas density

AAAS 2009 Plasma Wakefield Acceleration (PWFA)  Electron beam shock-excites plasma  Same scaling as Cerenkov wakes, maximum field scales in strength as  In “blowout” regime, plasma e-’s expelled by beam. Ion focusing + EM acceleration= plasma linac  Electron beam shock-excites plasma  Same scaling as Cerenkov wakes, maximum field scales in strength as  In “blowout” regime, plasma e-’s expelled by beam. Ion focusing + EM acceleration= plasma linac

AAAS 2009 Ultra-high gradient PWFA: E164 experiment at SLAC FFTB  Uses ultra-short beam (20  m)  Beam field ionization creates dense plasma  Over 4 GeV(!) energy gain over 10 cm: 40 GV/m fields  Self-injection of plasma e - s  X-rays from betatron oscillations  Uses ultra-short beam (20  m)  Beam field ionization creates dense plasma  Over 4 GeV(!) energy gain over 10 cm: 40 GV/m fields  Self-injection of plasma e - s  X-rays from betatron oscillations M. Hogan, et al. n e = 2.5x10 17 cm -3 plasma  New experiments: >10 GeV in 30 cm plasma (E167) Modified PRL cover

 Acceleration gradients of ~50 GV/m (3000 x SLAC)  Doubled 45 GeV beam energy in 1 m plasma  Required enormous infrastructure at SLAC  Not yet a “beam”  Acceleration gradients of ~50 GV/m (3000 x SLAC)  Doubled 45 GeV beam energy in 1 m plasma  Required enormous infrastructure at SLAC  Not yet a “beam” Nature Feb-2007 PWFA doubles SLAC energy

Future PWFA: whither FACET?  Further progress in PWFA (and dielectric) awaits FFTB replacement FACET program addresses critical questions for PWFA Use notch collimator to produce two bunches Plasma acceleration with narrow energy spread High-gradient positron acceleration

Plasma wave excitation with laser (LWFA): creation of very high quality beam  Trapped plasma electrons in LWFA give  n ~1 mm-mrad at N b >10 10  Narrow energy spreads can be produced  accelerating in plasma channels  Looks like a beam!  Less expensive than photo- injector/linac/compresor…  Very popular  LBL, Imperial, Ecole Polytech.

18 Channel guided laser-plasma accelerator (LWFA) has produced GeV beams!  Higher power laser  Lower density, longer plasma e - beam 1 GeV Capillary 3 cm 40 TW, 37 fs W.P. Leemans et. al, Nature Physics 2 (2006) 696

LBNL 10 GeV PWFA  Will be followed by staging at multi-GeV energies  10 GeV beam allow positron production, XFEL!  Will be followed by staging at multi-GeV energies  10 GeV beam allow positron production, XFEL! < 1 m 1000 TW 40 fs e - beam ~10 GeV Laser  Two-stage design  Need 40 J in 40 fs laser pulse  BELLA Project: 1 PW, 1 Hz laser Multi-GeV beams

ElectronPositron 1 TeV Laser m, 100 stages 1 TeV e-e- 10 GeV e+e m, 100 stages 10 GeV module: building block for a laser- plasma linear collider  Many experimental questions  Can begin to answer with ~$10-20M  BELLA is ~ head of world effort  Serious competition!

Beam quality needs to be controlled Naturally gives fsec pulses! “4D imaging with atomic resolution” Hot topic… Projects in EU, USA PW class laser gives multi-GeV electron beams in single stage: Table-top XFEL undulator

Fundamental Interaction Ultra-Relativistic optics Super hot plasma Nuclear Physics Astrophysics General relativity Ultra fast phenomena NLQED Relativistic Engineering ELI The Europeans think big: Extreme Light Infrastructure Exawatt Laser Secondary Beam Sources Electrons Positron ion Muon Neutrino Neutrons X rays  rays acceleratorsaccelerators Synchr.XfelSynchr.Xfel Attosecond optics Rel. Microelectronic Rel. Microphotonic Nuclear treatement Nuclear pharmacology Hadron therapy Radiotherapy Material science

1PW >1Hz 10PW, 1 Hz >100PW, 1Hz ELI ELI’s strategy for accelerator physics GeV e-beam.2 GeV p-beam 10 GeV e-beam GeV p-beam 50 GeV e-beam few GeV p-beam Beam lines for users e, p, X, g, etc… synchroton & XFEL communities Fundamental physics Multi stage accelerator Single stage accelerator Accelerator physics

Electron beam energy and laser power evolution? Laser Power (W) « conventional » technology Maximale Electrons Energy (MeV) Years LULI   RAL  LOA * LLNL UCLA  ILE ¤  KEK UCLA  ELIELI ELI * LLNL * LUND Lasers are doing better with their Moore’s law until now...

Towards an Integrated Scientific Project for European Researcher : ELI ELI

Advanced Accelerators  Advanced accelerators based on exotic new techniques have gone from concept to proof of application in last decade  US HEP led way, spin-offs to light sources  World-wide competition increasing  Excitement brings in energetic young researchers… must be on the cusp of important. US needs to reinvigorate!  Advanced accelerators based on exotic new techniques have gone from concept to proof of application in last decade  US HEP led way, spin-offs to light sources  World-wide competition increasing  Excitement brings in energetic young researchers… must be on the cusp of important. US needs to reinvigorate!