“Putting Beam Physics at the Forefront of Science”Work supported by DOE

Beam-Driven Plasma Based Advanced Acceleration Concepts

C.Joshi UCLA

IN HONOR OFProfessor Ron Davidson’s Leadership Role in HEDS

What are the compelling questions?

Frontiers in High Energy Density Physics-The X-Games of Contemporary Science(NRC Press 2003)

Frontiers for Discovery inHigh Energy Density PhysicsPrepared for OSTP byNational Task Force on High Energy Density Physics.

TASK FORCE WORKING GROUPS

A - HEDP in Astrophysical Systems Rosner (Chair), Arons, Baring, Lamb, Stone

B - Beam-Induced HEDP (RHIC, heavy ion fusion, high-intensity accelerators, etc.) Joshi (Chair), Jacak, Logan, Mellisinos, Zajc

S - HEDP in Stockpile Stewardship Facilities (Omega, Z, National Ignition Facility, etc.) Remington (Chair), Deeney, Hammer, Lee, Meyerhofer, Schneider, Silvera, Wilde

U - Ultrafast, Ultraintense Laser Science Ditmire (Chair), DiMauro, Falcone, Hill, Mori, Murnane

HEDP Task ForceChair:Davidson,Co-Chair:Katsouleas

Plasma Wakefield Plasma Wakefield AcceleratorsAccelerators(Blowout Regime)

• Plasma ion channel exerts restoring force => space charge oscillations

•Linear focusing force on beams (F/r=2ne2/m)

Accelerating Field 100 GeV/m , Focusing Gradients MT/m

• Space charge/ponderomotive force of thee beam/laser pulse displaces plasma electrons

Rosenzweig et. 1990 Pukhov and Meyer-te-vehn 2002 (Bubble)

++++++++++++++ ++++++++++++++++

----- --- ----------------

--------------

--------- ----

--- -------------------- - --

---- - -- ---

------ -

- -- ---- - - - - - ------ - -

- - - - --- --

- -- - - - - -

---- - ----

------

+ + + + + + + + + + ++ + + + + + + + + + + + + + ++ + + + + + + + + + + + + + +

+ + + + + + + + + + + + + + +-

- --

--- --

EzEz

drive beam

UCLA,USC,SLAC,ANL,FNAL,KEK,BNL

UCLA

ILC

Plasma Accelerator Progress“Accelerator Moore’s Law”

Working MachinesDoing physics

Max.Energy inLaser Experiments

High Energy Density Science with Ultra-relativistic Electron Beams:

Compelling Question

Can the ultra high electric fields in a beam-driven plasma wakefield be harnessed and sufficiently controlled to accelerate and focus high-quality, high-energy beams in compact devices?

Located in the FFTB

FFTB

e-

N=1-2· 1010

σz=0.1 mm=30 E GeV

Ionizing Laser Pulse

(193 )nm Li Plasma

ne≈6 · 10 15 cm-3

L≈30 cm

CerenkovRadiator

Streak Camera(1 )ps resolution

-X RayDiagnostic

Optical TransitionRadiators Dump

25 m

∫Cdt

!Not to scale

Spectrometer

25 m

Beam-Driven PWFA@ SLAC

BREAKING THE 1 GeV BARRIERWith 15 micron long bunches

0

2 104

4 104

6 104

8 104

1 105

1.2 105

-6 -4 -2 0 2

%CSpectra2.55e17

Plasma ONPlasma ONPlasma ONPlasma ONPlasma OFF

Relative Energy (GeV)

ne≈3.51017 cm-3 L≈10 cm, N≈ 1.81010

Charge Fraction at E>0: 8% of total charge!

ENERGY GAIN SCALING with PLASMA LENGTH

14GeV Energy Gain in less than 30cm !

U C L A

Some electrons double their energy in 84cm!Some electrons double their energy in 84cm!

U C L A

Linac running all out to deliver compressed 42GeV Electron Bunches to the plasmaRecord Energy GainHighest Energy Electrons Ever Produced @ SLACSignificant Advance in Demonstrating Potential of Plasma Accelerators

Nature vol 445,p741 (2007)

E-167: Energy Doubling with aPlasma Wakefield Accelerator in the FFTB

RAL

LBL Osaka

UCLA

E164X

ILC

Plasma Accelerator Progress“Accelerator Moore’s Law”

E167

LBNL

Working MachinesDoing physics

Max.Energy inPlasma Experiments

Goals and Relevance

To address critical issues for realizing a plasma-based accelerator at the energy frontier in the next decade.

To address critical issues for realizing a plasma-based accelerator at the energy frontier in the next decade.

New Compelling QuestionPlasma Afterburner for a conventional linear collider?

Plasma Afterburner for Linear Collider

Drive Beams Excite Ultrahigh-GradientAccelerating Structures in Plasmas

Trailing Beams Extract EnergyFrom These Structures

C.Joshi and T.Katsouleas Physics Today June 2003 p47

Conclusion:

Marx :HEPAP subpanel

“The challenge is to undertake and sustain the difficult and complex R&D needed to enable a feasible,cost and energy effective technology on the several decade horizon.Achieving these goals will require creativity and the development and maturation of new accelerator approaches and technologies.”

C.J. & T.K. thank their colleagues on experiments E164X and E167

Thanks Ron!!!

Keep asking us

What are the compelling Questions?

With very best wishes from

Plasma-Accelerators Community