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

Science Program at Test Facilities FACET ● ESTB ● NLCTA ● ASTA Mark J. Hogan SAREC Meeting at SLAC, July 2013

SLAC Electron Beam Test Facilities 5 MeV to 23 GeV 20-23 GeV 2-15 GeV 5 MeV & single e - FACET ASTA 60-220 MeV ESTB NLCTA Gorgeous view to physicist … 2

Very Productive User Run at FACET Every Program Expecting Publishable Results THz Reconstruction of Two- An Automated Method for Bunch Profile Dispersion Free Steering Switching Mechanisms in Ultrafast Electromagnetic Pulses Mono-energetic Acceleration in a Beam-driven Plasma Wakefield Accelerator Demonstration of Gigavolt- per-meter Accelerating Gradients in Dielectric Wakefield Accelerating Structures 3

NLCTA Continues to be an Incredibly Productive Facility λ ~ 0.8 µ m First Acceleration Observed in Laser Driven "Accelerator on a Chip" NLCTA E-163 Laser Room XTA Higher Brightness Beams Large Aperture RF Undulator with from X-Band Photoinjector Flexible Polarization, Wavelength Control 4

Echo (program) Has Enabled Broad Science at NLCTA EEHG in the energy space E. Hemsing, et al, Submitted to PRL (2013) The EEHG beamline and laser systems at NLCTA Tunable THz generation through EEHG enable broad range of diverse experiments Echo-7 Harmonics Coherent optical vortices from electron beams 1590 ¡nm ¡only, ¡V=0 7th 6th 4th 5th M. Dunning, et al. PRL 109, 074801 (2012) 1590 ¡nm ¡only, ¡V=85 ¡kV Cascaded Optical IFEL 1590 ¡nm ¡only, ¡V=170 ¡kV 1590 ¡nm ¡only, ¡V=255 ¡kV 795 ¡nm ¡+1590 ¡nm, ¡V=255 ¡kV E. Hemsing, et al, Nature Physics (2013) D. Xiang, et al, PRL 108, 024802 (2012) M. Dunning et al., PRL 110, 244801 (2013)

ASTA Program Benefits Near and Medium Term Applications • 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 Gun & Cathode Development 6

ESTB is a Unique Test Beam Resource • World’s only high-energy primary electron HERA-B e-Cal modules beam test for GEp(5) at J- Lab 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) 7

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) 8

10TW FACET Ionization Laser: Conceived, planned, installed, commissioned in < 7 months! Laser Transport in Klystron Gallery Laser System in new S20 Laser Room Molten Li Vapor Source Plasma Integration Optics on Beamline 9

E200 Uses Laser to Turn Lithium Vapor into a Plasma – Energy, Axicon Geometry Determine the Plasma Length This run (~250mJ): Coming in November (>500mJ): 40 ¡cm ¡long ¡argon ¡plasma from ¡2 ¡degree ¡axicon ¡at ¡UCLA ¡ 10

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) 11

FACET electron pump / x-ray probe experiments Use LWFA generated betatron radiation to probe extreme conditions generated by focussed, compressed FACET e - beam FACET electron beam 20 GeV, 3 nC Beam dump / e- spectrometer Filter to block laser x C LWFA 10‘s - r C a D y He gas jet Betatron x-rays MeV electrons Laser pulse Toroidal mirror Magnet Grating 20 TW / 30 fs Sample X-ray spectrometer 12

Now operating the tools to make and measure beams for the two bunch PWFA experiments X-band TCAV installed in Sector 20 2.44 m 1.00 〈Δ x 〉$ V ( t ) σ x e � σ z Δψ ≈ 60° 90° β c β p Profile Monitor OTRS:LI20:3075 24 � Mar � 2013 02:20:07 Measured Temporal Profile Measured Temporal Profile 2 Collimator OUT Collimator IN 1 Time y (mm) Time 0 � 1 � 2 � 3 � 2 � 1 0 1 2 3 x (mm) 13

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 200MeV Witness 20GeV Beam 14

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 Focusing and acceleration of positrons has been characterized at low densities Phys. Rev. Lett. 90 , 205002 (2003) • High-gradient positron acceleration is possible - Can use wake of an electron or positron beam • Need to iterate plasma source to minimize 5.7GeV in 39cm emittance growth but preserve high-gradients (hollow channels) • FACET will make first tests of high-gradient positron acceleration in the next couple years 16

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. 17

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. 18

Science/User Perspective • 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. 19