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?

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1017

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« conventional » technology M

axim

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ctro

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En

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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........

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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!