BeamNetUS is a national network of accelerator facilities that aims to provide broader access to the unique capabilities of accelerated particle beams. Two facilities at Brookhaven National Laboratory are part of the inaugural year of BeamNetUS, the Accelerator Test Facility (ATF) and the Low Energy Accelerator Development (LEAD) facility, and are scheduled to each host one BeamNetUS user experiment. The ATF features an RF photocathode electron LINAC, a femtosecond Ti:Sa laser, and a high-peak-power long-wave infrared (LWIR) laser. These tools can be synchronized for joint use or operated individually, facilitating the development of advanced beam manipulation and measurement techniques, accelerator and laser technologies, and the exploration of low-plasma-density regimes. The LEAD facility provides an ultrafast electron diffraction (UED) apparatus, utilizing an RF electron gun and Ti:Sa laser to enable dynamic studies of material structures, as well as investigations involving low-energy electron beams. In addition to these two accelerator facilities, Brookhaven National Laboratory provides administrative support for the network. Further expansion is planned for 2026, including both increased user hours at ATF and LEAD as well as the potential inclusion of several other facilities at the lab.

The Low Energy Accelerator Development (LEAD) Facility is a part of the Accelerators Facilities Division (AFD) of the Brookhaven National Laboratory (BNL). The facility has three capabilities and runs a program specifically targeting new collaborations for user-driven research. The first and the oldest of the capabilities is the Ultrafast Diffraction (UED) Capability. The other two are radiation-shielded bunkers. At the UED the deployment of a new stable solid-state modulator and klystron is in progress. The beamline updates are now going into place for a NASA Jet Propulsion Laboratory electron irradiator beamline for Single Event Effects (SEE) testing; and the capability for UED testing is being expanded. In both bunkers (153 and 77 sq. m) a range of cooling, air, electrical, and RF capabilities are presently being introduced. The first bunker will accommodate the Electron Cyclotron Resonance (eCRA) Demonstrator (a project together with Omega-P, R&D). The deployment is expected to start in the last quarter of 2025. The second bunker will accommodate the superconducting radiofrequency (SRF) photo-gun (a project by Euclid Techlabs, LLC) to be the electron beam source for an envisioned Ultrafast Electron Microscopy (UEM) Capability.

The Accelerator Test Facility (ATF) at BNL is the DOE Office of Science User Facility for Accelerator Stewardship, featuring a high-brightness, 80-MeV electron LINAC, near-infrared (NIR) lasers at 1.06 and 0.8 µm, and a 5-TW, 2-ps long-wave infrared (LWIR) 9.2-µm laser. ATF is advancing LWIR laser technology toward the multi-terawatt, femtosecond regime—a major milestone in this spectral domain. Its unique suite of synchronized or independently operated capabilities enables breakthroughs across a broad range of studies, from materials science to Homeland Security, and from advanced radiation sources to novel methods of particle acceleration. Research priorities are shaped by community input through ATF User Meetings and Science Planning Workshops. A key focus is leveraging the co-location of the LINAC and “multi-color” lasers to place ATF at the forefront of THz to hard x-ray radiation sources, plasma physics, and advanced accelerator R&D. In this approach, the LWIR laser drives plasma dynamics, while the LINAC and NIR lasers enable ultrafast probing of plasma fields and density, or controlled electron injection into plasma wakes. These efforts support global research into plasma instabilities relevant to astrophysics and inertial confinement fusion, as well as the development of future colliders and compact accelerators with potential industrial applications. Recent ATF user results highlight these advances.