advanced accelerators for future particle physics and light sources j. b. rosenzweig ucla department...
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Advanced Accelerators for Future Particle Physics and Light SourcesAdvanced Accelerators for Future Particle Physics and Light Sources
J. B. RosenzweigUCLA Department of Physics and Astronomy
AAAS Annual MeetingChicago, February 13, 2009
J. B. RosenzweigUCLA Department of Physics and Astronomy
AAAS Annual MeetingChicago, February 13, 2009
IntroductionIntroductionAccelerators have been central tools in science for three-fourths of a century
Enables research both fundamental and essentialHEP colliders: structure of matter at basic levelLight sources: structure of matter at functional level
Modern accelerators have extreme sophisticationPerformance optimized over decadesNew ideas in context of mature technologies
Accelerator science is a victim of its own successDemand 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 essentialHEP colliders: structure of matter at basic levelLight sources: structure of matter at functional level
Modern accelerators have extreme sophisticationPerformance optimized over decadesNew ideas in context of mature technologies
Accelerator science is a victim of its own successDemand 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
Historical schematic of accelerators: Particle physics leads, spin-offs follow quickly
Electrostatic Accelerators
Betatron
Cyclotron
Ion Linear Accelerators
1930 2030
Synchrotron CircularCollider
SuperconductingCircularCollider
Electron Linear Accelerators
Electron Linear Colliders
Muon Collider?
VLHC?Medicine Light sources
(3rd Generation)
Nuclear physics
X-ray FEL
Laser/Plasma Accelerators?
Ultra-High Energy LC?
FFAG,etc.
Colliders and the energy frontier
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
Limitations on collider energy
Synchrotron radiation power lossForces future e+-e- colliders to be linear
Large(!) circular machines for heavier particles
Consider muons for lepton colliders?
Scaling in size/costNear unitary limits
Few 104 m in dimensionFew $/€ 109
Synchrotron radiation power lossForces future e+-e- colliders to be linear
Large(!) circular machines for heavier particles
Consider muons for lepton colliders?
Scaling in size/costNear unitary limits
Few 104 m in dimensionFew $/€ 109
€
Ps ∝U 4
R2
Tevatron complex at FNAL (linacs, rings, buffalo…)27 km circumference
The energy challengeThe energy challenge
Avoid giantismCost above all
Higher fields give physics challengesCircular machines: magnetsLinear machines: high field acceleration
Enter new world of high energy density physicsBeam density, energy
Beam quality must increase to compensate smaller cross-section
Stored field energy
Avoid giantismCost above all
Higher fields give physics challengesCircular machines: magnetsLinear machines: high field acceleration
Enter new world of high energy density physicsBeam density, energy
Beam quality must increase to compensate smaller cross-section
Stored field energy
€
σ c ∝U−2
High energy densty in action at the
LHC
z
d
Linear accelerator schematic
High energy density in future e- linear
accelerators
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…
€
eE z /mcω ~ 1
TESLA SC cavity
Approaches to new collider paradigms
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 Nb3Sn magnet at LBNL
Muon collider schematic (R. Johnson)
2.5 km Linear Collider Segment
2.5 km Linear Collider Segment
μ +← postcoolers/preaccelerators μ−→
5 TeV μ μ+ − Collider 1 km radius, <L>~5E34
10 arcs separated vertically in one tunnel
HCC
300kW proton driver
Tgt
IR IR
Another Talk
HEP Spin-offf: X-ray SASE FEL based on SC RF linear accelerator
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
€
λr ≅λ u
2γ 21+ 1
2K2
[ ]
€
λu~1 Å radiation
10-15 GeV electrons
10 orders of magnitude
beyond 3rd gen X-ray light source!
10 orders of magnitude
beyond 3rd gen X-ray light source!
FNAL Colloquium
The optical acceleratorThe optical accelerator
Scale the linac from 1-10 cm to 1-10 μm 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 μm) planned at UCLA (340 μm)
Scale the linac from 1-10 cm to 1-10 μm 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 μm) planned at UCLA (340 μm)
Resonant dielectric structure schematic
Simulated fieldprofile (OOPIC);
half structure
e-beam
Laser power input
Inverse Cerenkov Acceleration
Inverse Cerenkov Acceleration
Coherent Cerenkov wakes can be extremely strongShort beam, small aperture; miniaturization…
SLAC FFTB, Nb=3E10, σz= 20 μm, a=50 μm, > 11 GV/m
Breakdown observed above 5.5 GV/m(!); on to plasma
Coherent Cerenkov wakes can be extremely strongShort beam, small aperture; miniaturization…
SLAC FFTB, Nb=3E10, σz= 20 μm, a=50 μm, > 11 GV/m
Breakdown observed above 5.5 GV/m(!); on to plasma
€
eE z,dec ≈−4Nbremec
2
a8π
ε −1εσ z + a
⎡
⎣ ⎢
⎤
⎦ ⎥
Simulated GV/m Cerenkov wakes for typical FFTB parameters (OOPIC)
AAAS 2009
Past the breakdown limit:Plasma Accelerators
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:
€
E(V/cm)∝ ne (cm-3)
Schematic of laser wakefieldAccelerator (LWFA)
€
E ∝100 GV/m, for ne =1018cm-3Ex: tenous gas density
AAAS 2009
Plasma Wakefield Acceleration (PWFA)
Plasma Wakefield Acceleration (PWFA)
Electron beam shock-excites plasmaSame 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 plasmaSame 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
€
E ∝Nbkp2 ∝Nbσ z
−2
AAAS 2009
Ultra-high gradient PWFA: E164 experiment at SLAC
FFTB
Ultra-high gradient PWFA: E164 experiment at SLAC
FFTBUses ultra-short beam (20 μm)
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 μm)
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.
ne=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 445 741 15-Feb-2007
PWFA doubles SLAC energyPWFA doubles SLAC energy
Future PWFA: whither FACET?Future PWFA: whither FACET?
Further progress in PWFA (and dielectric) awaits FFTB replacement
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
Plasma wave excitation with laser (LWFA): creation of very high
quality beam Trapped plasma electrons in LWFA give n~1 mm-mrad at Nb>1010
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.
Trapped plasma electrons in LWFA give n~1 mm-mrad at Nb>1010
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
€
ΔW[GeV] ~ I[W/cm2] n[cm-3]
e- beam
1 GeV
Capillary
3 cm
40 TW, 37 fs
W.P. Leemans et. al, Nature Physics 2 (2006) 696
BELLA @ LBNL 10 GeV PWFA
BELLA @ 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 m1000 TW40 fs
e- beam~10 GeV
Laser
Two-stage design
Need 40 J in 40 fs laser pulse
BELLA Project: 1 PW, 1 Hz laser
Electron Positron
1 TeVLaser200-500 m, 100 stages
1 TeV
e-
10 GeVe+
200-500 m, 100 stages
10 GeV module: building block for a laser-plasma linear collider
Many experimental questionsCan 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
ELIThe Europeans think big:Extreme Light Infrastructure
Exawatt Laser
The Europeans think big:Extreme Light Infrastructure
Exawatt Laser
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-beamGeV p-beam
50 GeV e-beamfew GeV p-beam
Beam lines for users e, p, X, g, etc…
synchroton & XFEL communities
Fundamental physicsMulti stage acceleratorSingle stage acceleratorAccelerator physics
Electron beam energy and laser power evolution?
1012
1013
1014
1015
1016
1017
Las
er P
ow
er (
W)
1
10
102
103
104
105
106
1930 1940 1950 1960 1970 1980 1990 2000 2010
« conventional » technology M
axim
ale
Ele
ctro
ns
En
erg
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MeV
)
Years
LULI
RAL LOA LOA*LLNL
UCLAILE ¤
KEK
UCLA
ELI
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 AcceleratorsAdvanced 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!