Just after 9 a.m. on Friday, Feb. 6, 2026, final beams of oxygen ions—oxygen atoms stripped of their electrons—circulated through the twin 2.4-mile-circumference rings of the Relativistic Heavy Ion Collider (RHIC) and crashed into one another at nearly the speed of light inside the collider’s two house-sized particle detectors, STAR and sPHENIX. RHIC, a nuclear physics research facility at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory has been smashing atoms since the summer of 2000. The final collisions cap a quarter century of remarkable experiments using 10 different atomic species colliding over a wide range of energies in different configurations.
The RHIC program has produced groundbreaking discoveries about the building blocks of matter and the nature of proton spin and technological advances in accelerators, detectors, and computing that have far surpassed scientists’ expectations when this discovery machine first turned on.
“RHIC has been one of the most successful user facilities operated by the DOE Office of Science, serving thousands of scientists from across the nation and around the globe,” said DOE Under Secretary for Science Darío Gil. “Supporting these one-of-a-kind research facilities pushes the limits of technology and expands our understanding of our world through transformational science—central pillars of DOE’s mission to ensure America’s security and prosperity.”
