Antihelium-4: Physicists nab new record for heaviest antimatter

Members of the international STAR collaboration at the Relativistic Heavy Ion Collider — a particle accelerator used to recreate and study conditions of the early universe at the U.S. Department of Energy’s Brookhaven National Laboratory — have detected the antimatter partner of the helium nucleus: antihelium-4.

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Antihelium-4: Physicists nab new record for heaviest antimatter