LEA@APS - Linac Extension Area at the Advanced Photon Source
The Linac Extension Area (LEA) at the Advanced Photon Source (APS) is a one-of-a-kind testbed for advanced accelerator research and development. It provides access to ~0.5 GeV electron beams generated from a variety of electron sources, including single electron bunches or bunch trains, which are accelerated and compressed in the APS linac. This versatility makes LEA an invaluable resource for exploring a wide range of accelerator physics and technology applications. LEA’s capabilities include high-quality ~0.5 GeV electron beams produced by a photoinjector or bunch trains from a thermionic electron source. The facility also features a low-beta insertion, enabling precision testing of small-aperture components, which is critical for the development of next-generation accelerator technologies. Additionally, LEA is equipped with a co-located high-power RF system and a dedicated laser room, providing the infrastructure necessary for advanced beam manipulation, diagnostics, and synchronization experiments. With its unique combination of high-energy electron beams, precision testing capabilities, and state-of-the-art infrastructure, LEA serves as a critical platform for pioneering R&D in accelerator science, supporting innovations in compact radiation sources, beam dynamics, and advanced diagnostics.
Facility bio
Name of Facility: LEA@APS
Laboratory: Argonne National Laboratory
Address: 9700 S. Cass Avenue, Argonne, IL 60439
Point of Contact: Yine Sun
Facility website:
Publications list:
| Parameter | Value |
|---|---|
| Beam Type | Electrons |
| Beam Energy | 400 - 500 MeV |
| Repetition Rate | 1 - 30 Hz |
| Bunch Charge | 0.1 - 1.5 nC |
| Bunch Length (sigma) | 100 μm - 1 mm |
| Beam spot size (sigma) | 50 μm - 1 mm |
| Peak Current (photoemission) | ~2 kA |
Science specialists: APS/ASD has expertise in beam dynamics, advanced acceleration (w/ AWA group) and high-power RF system. It can provide support for instrumentation and controls.
Capabilities
Facility Features:
Located at the end of the APS linac
Adjacent to two high-power 2.856-GHz RF sources (50 MW and 30 MW) and a laser room (currently empty)
Beamline comprising quadrupole, spectrometer, and beam diagnostics (charge, beam distribution, position monitors)
Currently configured with a section to accommodate a “device under test” with focused beam
Beams from the APS photoinjector or thermionic electron source can be sent to LEA
EPICS-based control system → remote run possible
Facility is not regularly operated, it can be accessed to install experiment but operation must be coordinated with APS operation schedule (beam time needs to be requested during the weekly machine studies)
Additional beam time may be available in the future when fast interleaving operation between SR and LEA is implemented.
Ideal Experiment
Relativistic beam and high-power klystron
Testing of high-gradient S-band structures with beams from LEA and powered by ss-modulator driven high-power klystron, beam-wave interaction in small-aperture (THz) structures.
Bring your own structure or electron sources; example planned study of S-band version of C3 structures by SLAC.
R&D on radiation sources
Radiation source with available undulator (old APS modules) or possibly using laser-based manipulation.
Bring your own laser, undulator system.
