Science Program at Test Facilities FACET ESTB NLCTA ASTA Mark J. - - PowerPoint PPT Presentation

Science Program at Test Facilities

Mark J. Hogan SAREC Meeting at SLAC, July 2013

FACET ● ESTB ● NLCTA ● ASTA

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ESTB NLCTA FACET ASTA 20-23 GeV 2-15 GeV & single e- 5 MeV 60-220 MeV

Gorgeous view to physicist…

SLAC Electron Beam Test Facilities 5 MeV to 23 GeV

Very Productive User Run at FACET Every Program Expecting Publishable Results

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Switching Mechanisms in Ultrafast Electromagnetic Pulses Demonstration of Gigavolt- per-meter Accelerating Gradients in Dielectric Wakefield Accelerating Structures An Automated Method for Dispersion Free Steering THz Reconstruction of Two- Bunch Profile Mono-energetic Acceleration in a Beam-driven Plasma Wakefield Accelerator

NLCTA Continues to be an Incredibly Productive Facility

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First Acceleration Observed in Laser Driven "Accelerator on a Chip"

E-163 XTA

Higher Brightness Beams from X-Band Photoinjector Large Aperture RF Undulator with Flexible Polarization, Wavelength Control

Laser Room

λ ~ 0.8µm

NLCTA

1590 ¡nm ¡only, ¡V=0 1590 ¡nm ¡only, ¡V=85 ¡kV 1590 ¡nm ¡only, ¡V=170 ¡kV 1590 ¡nm ¡only, ¡V=255 ¡kV 795 ¡nm ¡+1590 ¡nm, ¡V=255 ¡kV 4th 5th 6th 7th

• D. Xiang, et al, PRL 108, 024802 (2012)

Coherent optical vortices from electron beams Echo-7 Harmonics EEHG in the energy space Cascaded Optical IFEL

The EEHG beamline and laser systems at NLCTA enable broad range of diverse experiments

Tunable THz generation through EEHG

• M. Dunning, et al. PRL 109, 074801 (2012)
• M. Dunning et al., PRL 110, 244801 (2013)
• E. Hemsing, et al, Nature Physics (2013)
• E. Hemsing, et al, Submitted to PRL (2013)

Echo (program) Has Enabled Broad Science at NLCTA

ASTA Program Benefits Near and Medium Term Applications

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Gun & Cathode Development

• Study effects of material, geometry under high-power
• Cathode & gun development with focus on LCLS
• Commission gun for LCLS-II

Copper-silver structures operating reliably above 175 MV/m

ESTB is a Unique Test Beam Resource

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• World’s only high-energy primary electron

beam for large scale Linear Collider MDI and beam instrumentation studies

• Exceptionally clean and well-defined

primary and secondary electron beams for detector development

Test of a RICH-Prototype Based on CsI- GEMs for an Electron-Ion Collider (T-507) HERA-B e-Cal modules beam test for GEp(5) at J- Lab

Evolution of FACET to Enable New Science

• Constructed with long term goal of PWFA demonstration
• Operates as a National User Facility
• FACET facility developments offer shared benefit to broader

community

• All SLAC accelerator test facilities will operate as user facilities

in the future offering mutually beneficial operations of test facilities: experimental expertise and user experience => efficiency

• Upgrades benefit all all programs (TCAV, laser, SS window,

motors)

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10TW FACET Ionization Laser: Conceived, planned, installed, commissioned in < 7 months!

Laser System in new S20 Laser Room Laser Transport in Klystron Gallery Plasma Integration Optics on Beamline Molten Li Vapor Source

E200 Uses Laser to Turn Lithium Vapor into a Plasma – Energy, Axicon Geometry Determine the Plasma Length

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40 ¡cm ¡long ¡argon ¡plasma from ¡2 ¡degree ¡axicon ¡at ¡UCLA ¡

This run (~250mJ): Coming in November (>500mJ):

E-210 Trojan Horse needs Better Synchronization

• Implement laser-electron beam timing diagnostic via EOS
• Release electrons in plasma wave with focused, ~mJ, synchronized laser

pulse to generate highest quality witness beam (∊n <10-8 m-rad)

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Laser pulse 20 TW / 30 fs

Toroidal mirror

He gas jet Magnet

x

• r

a y C C D

Grating Betatron x-rays LWFA 10‘s MeV electrons

FACET electron beam 20 GeV, 3 nC

Filter to block laser Beam dump / e- spectrometer

Sample X-ray spectrometer

Use LWFA generated betatron radiation to probe extreme conditions generated by focussed, compressed FACET e- beam

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FACET electron pump / x-ray probe experiments

Now operating the tools to make and measure beams for the two bunch PWFA experiments

X-band TCAV installed in Sector 20

13 V(t) e σz σx 2.44 m βc βp 〈Δx〉$ Δψ ≈ 60° 1.00 90°

Time

Measured Temporal Profile

3 2 1 1 2 3 2 1 1 2 x (mm) y (mm) Profile Monitor OTRS:LI20:3075 24Mar2013 02:20:07

Time

Measured Temporal Profile

Collimator IN Collimator OUT

Exploring Addition of a Photoinjector in 2015 Independent Injection/control of Witness Bunch

• 50-100MeV, injected for staging dielectric & plasma accelerators
• Use 100 fold difference in energy with bend/chicane to merge
• Upgrade dumpline to dump spent beam and preserve emittance of

accelerated beam

• Need feedback on beam parameters from users

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20GeV Beam 200MeV Witness

Single Shot Emittance Measurement with Interference of Edge Radiation

E-210, witness injector experiments will require new beamline for better emittance measurements

Commissioning Positron Systems in FY14 Run

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5.7GeV in 39cm

Focusing and acceleration of positrons has been characterized at low densities

• High-gradient positron acceleration is possible
• Can use wake of an electron or positron beam
• Need to iterate plasma source to minimize

emittance growth but preserve high-gradients (hollow channels)

• FACET will make first tests of high-gradient

positron acceleration in the next couple years

• Phys. Rev. Lett. 90, 205002 (2003)

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New proposals for 2013 SAREC review (FACET)

• High-quality witness bunch generation and acceleration in a beam-driven

wakefield accelerator by density down-ramp injection, Jens Osterhoff, DESY

• Temporal Limits of Electron-Phonon Interaction in Metal-Insulator

Transitions, Electro-magnetostriction and Plastic Deformation, Ioan Tudosa, University of Pennsylvania

• Single-Shot Imaging of THz-Induced Switching in Information Technology

Materials, Hermann Dürr, Stanford

• Proposed Experiment for Single Shot Femtosecond Beam Pulse Length

Measurements at FACET using the Angular Distribution of Coherent Diffraction Radiation, Ralph Fiorito, University of Maryland

• Monochromatic 10 MeV Gammas by a Miniature Undulator, for

Experiments at the Intersection of Photonuclear and Materials Science. Michael Di Rosa, LANL

• Gyromonotron as an instrument for electron beam cooling in accelerators,

Volodymyr Khoruzhi, Kharkov Institute of Physics and Technology New proposals are direct result of the high quality of FY13 run.

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New Proposals for 2013 SAREC Review (NLCTA, ESTB, ASTA)

• Biological effectiveness of very high-energy electron radiation therapy

– implications for a novel radiation treatment system for cancer, Billy

• W. Loo Jr, MD, Department of Radiation Oncology, Stanford
• Suppression of Spontaneous Undulator Radiation at NLCTA, Daniel

Ratner, SLAC

• Development of Electron Radiography for Material Science, Frank E.

Merrill, LANL

• Advanced IFEL bunching experiments at NLCTA, P. Musumeci, UCLA
• Channeling and Volume-Reflection Studies of High-Energy Electrons

in Crystals, H.-Ulrich (Uli) Wienands, SLAC

• High gainX-band active SLED-II pulse compression experiment, Jay L.

Hirshfield , Omega-P, Inc. SLAC is transitioning to operate all of its test facilities in the “user facility” mode with external program advisory committees reviews.

Science/User Perspective

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• FACET development to address needs of all programs (TCAV, laser, SS

window, motors = addressing needs of the users)

• It was great run at FACET, next run is coming, short time to publish,

necessary for community/DOE to support run time.

• New directions (gamma beams, radiography, …diagnostics)
• Wide range of facilities available at SLAC offer one stop shopping for users
• FACET operates as a National User Facility and is living up to its’ potential

with machine performance routinely exceeding expectations

• Upgrades in the works will benefit PWFA program but also serve the entire

community and help broaden the program

• Offer one stop shopping for users => efficient user experience
• NLCTA transition to user operation mode will focus on reliability and

predictable, well characterized beam quality.