UW physicists, CERN announce discovery of Higgs boson interactions

A researcher works on a semiconductor tracker barrel for the ATLAS experiment at the Large Hadron Collider. CERN The international particle accelerator collaboration CERN announced Monday, June 4, that two experiments at the Large Hadron Collider discovered a link between the two heaviest known particles: the top quark and the Higgs boson. University of Wisconsin-Madison physicists are members of the CMS and ATLAS experiments at CERN, which jointly discovered the Higgs boson in 2012. The same two experiments have now seen simultaneous production of both the Higgs boson and the top quark during a rare subatomic process. This is the first time scientists have measured the Higgs boson's direct interaction with top quarks. Studying these particles gives clues about the nature of matter and mass in the universe. "The members of the CMS collaboration are very pleased to be publishing the first observation of direct coupling of the Higgs boson to the top quark and that the ATLAS experiment also observes this," says Wesley Smith , a professor of physics and the leader of the Particle Physics Group and the CMS program at UW-Madison.