J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

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Highlights of the 47 th ICFA Workshop on the Physics and Applications of High Brightness Electron Beams J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

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Highlights of the 47 th ICFA Workshop on the Physics and Applications of High Brightness Electron Beams. J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010. Physics and Applications of High Brightness Electron Beams Maui, November 16-19, 2009. - PowerPoint PPT Presentation

Transcript of J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Page 1: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Highlights of the 47th ICFA Workshop on the Physics and

Applications of High Brightness Electron Beams

J.B. RosenzweigUCLA Dept. of Physics and Astronomy

Future Light Sources 2010SLAC March 3, 2010

Page 2: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Physics and Applications of High Brightness Electron BeamsMaui, November 16-19, 2009

Latest in series resulting from joining “High Brightness” and “Arcidosso” workshops

Endorsed by ICFA subpanels on Beam Dynamics and Advanced and Novel Accelerators

Mid-Pacific setting to encourage

Asian participation

Page 3: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

CommitteesOrganizing committee Co-chairs J. Rosenzweig (UCLA) L. Palumbo (Univ. Roma “La

Sapienza”) M. Uesaka (U. Tokyo)

L. Serafini (INFN-Milano) C. Brau (Univ. Vanderbilt) H. Braun (PSI) K-J. Kim (UC/ANL) G. Dattoli (ENEA) S. Milton (Sinc. Trieste/ANL) S. Chattopadhay (Cockroft Inst.) P. Emma (SLAC) J. Rossbach (DESY) W. Leemans (LBNL) V. Yakimenko (BNL)

Program committee  M. Ferrario (INFN-LNF), Chair

C. Pellegrini (UCLA) W. Barletta (MIT) Z. Huang (SLAC) G. Krafft (JLAB) M. Poole (Daresbury) L. Giannessi (ENEA) X. Wang (BNL) R. Kishek (Univ. Maryland) M. Eriksson (MAXLAB) F. Gruner (LMU/MPQ) T. Kamps (BESSY) D. Giulietti (Univ. Pisa) G. Hoffstaetter (Cornell) F. Stephan (DESY) T. Shintake (SPring-8)

Page 4: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

History1999-Los Angeles: The Physics of High Brightness

Beams - merging of ion/electron communities2002-Chia Laguna: The Physics of and

Applications High Brightness Beams – joining of Arcidosso series, light source applicaitons

2005-Erice: The Physics of and Applications High Brightness Beams. Theme: birth of the SASE FEL

2009-Maui: The Physics of and Applications High Brightness Beams. Theme: New directions, plasma sources, etc.

Page 5: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

StatisticsThe workshop had 105 registered attendees from across

the beam physics community, among them 10 students with partial support from the workshop.

The workshop received financial contributions from ANL, LBNL Sincrotrone Trieste, SLAC, UCLA, and the Univ. of Tokyo.

Conference secretariat headed by Carly Nguyen of UCLA, and included Francesa Casarin and Daniela Ferrucci of INFNLNF.

Further information on the workshop is available at:http://pbpl.physics.ucla.edu/HBEB/index.html

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MissionHigh brightness electron beams are playing an increasingly critical role in two frontier fields that are now yielding results that provoke considerable excitement and activity across the scientific community: radiation generation methods and advanced acceleration schemes. Such cutting edge radiation production methods include variations on the revolutionary 4th generation device, the free-electron laser, as well as inverse Compton scattering of intense lasers. These diverse approaches are thus able to create high peak and high average power light sources, with applications in ultrafast sciences and the Å level, as well as in nuclear and high-energy physics. Likewise, high brightness beams are at the center of many future accelerator schemes, e.g. based on high gradient electron and laser wakefields. Indeed, laser wakefield accelerators are now entering the proof-of-application phase, where unique light sources based on advanced acceleration schemes are enabled. The goal of this workshop is to provide a comparative study of the generation, manipulating, modeling and measuring of high brightness electron beams, and the multitude of underlying, interdisciplinary methods linking the physics of these beam systems to the physics of advanced applications.

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Plenary talks and working groups

1. Sources, including photoinjectors and plasma-based sources2. Manipulation and diagnosis of high brightness beams 3. Theory and modeling, simulation challenges4. Applications of high brightness beams in advanced accelerators and light sources.

* November 16 LCLS Injector Performance and Impact on Lasing - D. Dowell High Brightness Beam Measurements at PITZ - F. Stephan Superconducting RF Photoinjector Development - T. Kamps Intense Space Charge Effects of Relevance to FEL Injectors - R. Kishek On the Control of e-Beam Parameter with Laser Plasma Accelerators - V. Malka Overview of Advanced Cathodes for HBB - L. Cultrera Novel high brightness beyond photocathodes - C. Brau * November 17 Advanced Laser Pulse Shaping - H. Tomizawa Photoinjector Blow Out Regime Experiments at UCLA - P. Musumeci Velocity Bunching at SPARC - D. Filippetto Generation of Train of Short Electron Pulses for Wakefield Expts. - P. Muggli Beam Diagnosis at the Fs frontier - H. Loos Tomographic Phase-Space Mapping of High-Brightness Beams - D. Stratakis X-ray FEL Oscillator: Promises and Challenges - K-J. Kim

* November 18 Emittance Compensation Theory & Experimental Results - C. Wang Thermal Beam Equilibria in Periodic Focusing Fields - C. Chen Physics of a 10 GeV laser-plasma accelerator - E. Esarey Brightness Characterization of Electro Beams from Plasma Injectors - A. Rossi Echo harmonic-techniques for Introducing NM Beam Structures - D. Xiang Overview of LWFA Experiments - W. Leemans High Average Power, High Brightness Electron Beam Sources - F. Sannibale

* November 19 Overview of Thomson/Compton Sources - R. Kuroda Plasma and Dielectric Wakefield Acceleration Experiments at SLAC - M. Hogan Sub-fs Electron Pulses for FEL and PWFA applications - J. Rosenzweig Soft X-ray Undulator Radiation from Laser Accelerated Electrons - M. Fuchs Prospects for a Table Top FEL - C. Schroeder Laser-structure accelerators - B. Cowan The Coolest Beam in the World - J. Luiten

Lets proceed from the cathode forward….

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Overview of photocathodes- L. Cultrera (INFN-KNF)

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Fundamental tension between QE and thermal emittance…

Mitigated by using semi-conductor cathodes… but these are slower

Page 10: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Coatings on metal photocathodes: improving lifetime

Wide band-gap thin film coatings give interesting results Example: CsBr, transmissive

at 257 nm

MgF coatings improve Schottky by field inside coating

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Emission in the visible: YttriumPhotoemission at 400 nmLifetime issues in SPARC studies

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Superconducting guns: Pb cathodes

Lead is excellent candidate cathode for SC gunsUsual tradeoff between QE and thermal emittance

J. Smedley, T. Rao and J Sekutowicz, Phys. Rev. ST Accel. Beams, 11, 13502 (2008)

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Semiconductor photocathodesHigh QE through electron-phonon scattering (slow)Coatings improve lifetime here tooPolarization with strained GaAs

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Frontier: diamond amplifier cathode

Gain over 200; beams emitted

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Life after photocathodes-C. Brau (Vanderbilt)

Field emission approaches quantum brightness limit

Dedicated study of diamond tips…

6 nm tip radius

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Improvements through gated arrayDiamond FEA already FEL quality (high average

power oscillator)

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Diamond FEAs to be installed in SC guns

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Carbon nanotubes approach quantum emission limitCentral role of adsorbate atoms in mediating

emission

Page 19: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

The coolest beams in the world

-O.J. Luiten (Eindhoven)Standard photocathodes at othe 0.1-1 eV

temperatureRydberg atom gas in laser trap gives orders of

magnitude improvement possibility

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Ultra-cold beam experimentsFirst tests give three orders of magnitude

temperature improvement

Page 21: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Immediate applicationsUltra cold ion beamsUltra-fast electron diffraction

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Ultrashort laser pulses on the cathode: blow-out regime and multiphoton photoemission – P. Musumeci (UCLA)Blowout regime dynamically produces high quality

electron bunch – ellipsoidal shapeVery high 6D brightness with low Q

Deflector enabled observations

Page 23: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Application: ultra-relativistic electron diffraction

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Multiphoton photoemissionPhotoemission observed in IR!Lower efficiency compensated by regaining uv

conversion losses

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Superconducting RF Photoinjector Development -- T. Kamps (HZB)Obvious approach to high average current

photoinjectors for FEL BNL, Berlin, Dresden…

Challenges: cathode, beam focusing

Page 26: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

High Average Power, High Brightness Electron Beam Sources - F. Sannibale (LBNL) Normal conducting option presented Cooling gives strong field limitations

Page 27: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

LCLS Injector Performance and Impact on Lasing- D. Dowell (SLAC)Remains the gold standardMany problems in high field photoinjectors

mitigated

Page 28: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Very low charge mode at LCLSHigher brightness, ultra-short pulse for advanced

FEL

Page 29: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Velocity bunching at SPARC –D. Fillipetto (INFN-LNF)Advanced compression technique, avoids “the

bends”Compression x3 with little emittance growth

Longitudinal phase space schematic for velocity bunching

Page 30: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

An X-Ray FEL Oscillator: Promises and Challenges -- Kwang-Je Kim (Chicago/ANL)

An X-ray pulse is stored in a diamond cavity multi-pass gain & spectral cleaning Provide transform limited BW Zig-zag path cavity for wavelength tuning

Page 31: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Compelling brightness argument

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Low charge, high brightness beams… again

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Plasma and Dielectric WakefieldAcceleration Experiments at -- M. Hogan

Enormous accomplishments at FFTB, looking towards FACET

Page 34: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

A Light Source Scenario using Dielectric Wakes

Pulse train may not be needed or desirable…

Instead, look for enhanced transformer ratio with ramped beam

Does this work with multi-mode DWA?

Scenario: 500-1000 MeV ramped driver; 5-10 GeV FEL injector in <10 m

Ramped beam R>>2

Symmetric beam R<2

Ramped beam R>>2

Page 35: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

A FACET scenarioCharge: 3 nCRamp: L=2.5 mmEnergy: 500 MeV Structure: a=100 mm, b=100 mm, e=3.8

Fundamental f=0.74 THzPerformance: >GV/m accel.,

R=24 (12 GeV possible)Sag in wake due to multi-mode

Page 36: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

TV/m plasma wakefield accelerator using low charge, ultra-short beam –-J. Rosenzweig, UCLA

Original proposal to scale beam charge to pC levelVelocity + chicane bunching preserves <3-6 E-8

emittance

Single spike FEL, sub-fs (few 100 attosecond) operation

B = 2 ×1017 A/m2

ΔωΔt = 1.67

Page 37: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Use Table-top XFEL undulator?LMU MPQ-centered collaboration (BESSY, LBNL, UCLA, etc.)UCLA collaboration on advanced hybrid cryo-undulator (Pr-based,

SmCo sheath, Fe pole), 9 mm period, >2 T

Need short lu high field undulator for X-rays @1 GeV – critical for traditional linac sources too…

With ultra-high brightness beam, one may have very compact, extended capability FELs

Simulated 9 mm cryounduator performance at 30K (Maxwell, Radia, Pandira)

Page 38: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Example: SPARX w/sub-fs pulseWavelength reduction (3 nm->6.5 Å)Ultra-short saturation length (10 m)LCLS photon reach at 2.1 GeV on 5th harmonic

Simulated performance on fundamentalMW peak power at 1.5 Å, 5th harmonic

Page 39: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Example: LCLS w/sub-fs pulseUse even shorter 0.25 pC beam, 150 as pulse

Single spike w/standard LCLS undulator

Obtain ultra-compact “LCLS” at 4.3 GeVExtend energy reach to 83 keV (0.15Å)

Gain evolution for 1.5 Å 4.3 GeV (0.25 pC)Gain evolution at

13.6 GeV, 0.15 Å

Page 40: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Ultra-short, high brightness beam:IR wavelength PWFA

Ultra-high brightness, fs beams impact HEP strongly…Use 20 pC LCLS beam in high n plasmaIn “blowout” regime: total rarefaction of plasma e-sBeam denser than plasmaVery nonlinear plasma dynamicsPure ion column focusing for e-sLinac-style EM acceleration General measure of nonlinearity:

˜ Q ≡Nbkp

3

n0

= 4πkpreNb

<<1, linear regime>1, nonlinear "blowout" ⎧ ⎨ ⎩

MAGIC simulation of blowout PWFA case

-1.5

-1

-0.5

0

0.5

1

1.5

0 0.5 1 1.5 2 2.5

.

F/m

ec

ω

p

k

p

r

F

z

F

r

Wakes in blown out region

Page 41: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Optimized excitation at LCLSBeam must be short and narrow compared to plasma skin depth In this case implies , blowout With 2 fs LCLS beam we should choose For 20 pC beam, we haveLinear “Cerenkov” scaling

1 TV/m fields (converted Er)Collaboration initiated

UCLA-SLAC-USC Basic science: coherent radiation, BSI ionization

nb >n0

σ r <kp−1

σz <kp−1

n0 = 7 ×1019 cm-3

˜ Q = 7

OOPIC simulation of LCLS case

eEz,dec≅4e2Nbσ z

2

Page 42: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Laser-driven undulator source -- M. Fuchs (MPQ)

Plasma acceleration gives 1st observed X-raysW. Leemans discusses application further…

Page 43: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

Aloha from MauiMahalo: thank to all for coming, and contributing at such

a high levelLook for updates on publications on website

JACOW submission formalities, open soon Particular emphasis on invited, summary talks (6 pages)

PRSTAB special option

To the farther future...

Page 44: J.B. Rosenzweig UCLA Dept. of Physics and Astronomy Future Light Sources 2010 SLAC March 3, 2010

First suggestion (from D. Stratakis): Crete 2011We are open to all ideas that fit the theme!