FRIB successfully delivered a 20 kilowatt (kW) uranium-238 beam on target during accelerator operations on 13 March.
This record beam power doubled the previous world record of 10kW uranium beam power. It comes less than three years after the start of FRIB operations and is part of the progress toward FRIB’s full capability.
During operations, FRIB’s beam-energy feedback system was used to monitor and compensate for the energy variation caused by the thickness fluctuation of the liquid-lithium charge stripper. The feedback system includes a super-conducting accelerating cavity and a bunching cavity upstream of the charge stripper that correct the beam energy and arrival phase variations.
The milestone of accelerating the heavier uranium-238 beam is the second record set at FRIB in the past eight months. In July 2024, scientists delivered a record 22 kW selenium-82 beam during a test. Selenium is a lighter ion than uranium and easier to accelerate, and the accomplishment set the stage for the latest feat by FRIB’s accelerator.
According to FRIB Accelerator Systems Division Director Jie Wei, the main challenge with using heavy ions like uranium is dealing with the high energy released when the beam hits another material, such as the liquid-lithium charge stripper, which varies in thickness ever so slightly over time.
“We reached the world record with uniquely developed technologies – like the liquid-lithium charge stripper – and simultaneous acceleration of multiple charge states,” said Wei.
FRIB’s approach to enhancing discovery opportunities involves operating safely while anticipating and avoiding risks as it increases the primary beam intensity. FRIB maintains management systems externally registered by NSF International Strategic Registrations to ISO standards to ensure compliance and quality to external regulatory standards.
Beam information available online
FRIB has developed several primary beams and energies to increase yields for rare isotope beams.
Read more about the specific beam currents by isotope and energy on the Beams page.