FACET-II - Facility for Advanced Accelerator Experimental Tests

FACET-II is an Office of Science National User Facility. FACET-II provides beams optimized for the next generation of Plasma Wakefield Acceleration experiments and is the only facility in the world capable of providing 10 GeV electron beams in support of accelerator science R&D. It allocates roughly half of the beam time towards investigating plasma wakefield acceleration in support of the R&D roadmaps defined in the DOE Advanced Accelerator Development Strategy Report [6]. Primary elements of this program include demonstration of a 10 GeV plasma stage with preserved beam quality, development of ultra-high brightness beams from plasma-based injectors and developing high-intensity X-ray and Gamma-ray sources. The other half is dedicated to a diverse set of research programs enabled by high-energy high-intensity electron beams and their interaction with lasers, plasmas and solids. Novel diagnostics to characterize the extreme beams are being developed combining beam-physics, machine learning and artificial intelligence. Future upgrades to deliver 10 GeV high intensity positron beams and upgrades to the 10 TW experimental laser systems are under development to exploit the full scientific potential of the facility.

Facility bio

Name of Facility: Facility for Advanced Accelerator Experimental Tests - FACET-II

Laboratory: SLAC National Accelerator Laboratory

Address: 2575 Sand Hill Road, Menlo Park, CA 94025

Point of Contact: Ivan Rajkovic

Facility website: Link

Publications list: Link

FACET-II is a DOE National User Facility and access for longer campaigns than what is available through BeamNetUS can be secured through its standard proposal review process.

FACET-II Beam Parameters- nominal values given, range in brackets
Parameter Value
Beam Type Electrons: polarized and unpolarized
Beam Energy 10 GeV
Repetition Rate 10 Hz
(1 - 30 Hz)
Bunch Charge 2 nC
(0.5 - 3 nC)
Bunch Length 20 μm
(1 - 100 μm)
Beam spot size 30 μm
(5 - 200 μm)
Experimental laser pulse energy 250 mJ
(10 - 350 mJ)
Experimental laser pulse duration 50 fs
(50 -600 fs)

Capabilities

Science specialists:

FACET-II staff work within the FACET and Test Facilities Division in the Accelerator Directorate (AD) at SLAC. AD operates the LCLS, LCLS-II, FACET-II, the NLCTA and the ASTA MeV-UED facility. By working at SLAC we can draw on expertise from across the lab in accelerator operations, beamline design, accelerator modeling, laser system engineering, vacuum, mechanical, design, controls, AI/ML as well as couple into the broader expertise of our Users and University colleagues with additional expertise in plasma sources and advanced computation. 

Available tools:

  • 10GeV e- with >100kA peak current focusses to <20µm size transversely

  • 10 TW experimental laser

  • High-vacuum chambers with motorized stages

  • A variety of plasma sources

  • Photon and electron diagnostics from the visible to MeV photon energies

Ideal Experiment

The ideal experiment at FACET-II will involve something that takes advantage of the extreme fields of the focused electron beam to reveal fundamental physics processes or identify new mechanism to diagnose the electron beam itself. Solid, gas pr plasma targets can be pumped, probed or pulverized by the beam fields and then characterized in situ with optical cameras, diagnostic laser probes or post-mortem inspection of samples. Access time to the FACET-II experimental area is infrequent and of limited duration so experiments should be bench tested and minimal hands-on preparation or alignment once installed.