A particle smasher has created antihyperhelium-4, the heaviest antimatter nucleus ever made in a physics labDuncan Walker/Getty Images Another antimatter record has been broken. In the smash-up of very energetic lead ions, researchers have uncovered evidence of the heaviest antimatter version of an atomic nucleus ever seen. In 2024, researchers from the STAR Collaboration at Brookhaven National Laboratory’s Relativistic Heavy Ion Collider (RHIC) in New York reported briefly creating a then unprecedentedly heavy antimatter nucleus called antihyperhydrogen-4. Now, Benjamin Dönigus at Goethe University Frankfurt…