ATLAS searches for pairs of Higgs bosons in a rare particle decay

Since the Higgs boson was discovered in 2012, scientists at the Large Hadron Collider (LHC) have been studying the properties of this very special particle and its relation to the fundamental mechanism essential to the generation of mass of elementary particles. One property that remains to be experimentally verified is whether the Higgs boson is able to couple to itself, known as self-coupling. Such an interaction would contribute to the production of a pair of Higgs bosons in the LHC’s high-energy proton–proton collisions, an incredibly rare process in the Standard Model—more than 1000 times rarer than the production of a single Higgs boson! Measuring a Higgs boson self-coupling that is different from the predicted value would have important consequences; the universe might be able to transition into a lower energy state and the laws that govern the interactions of matter could take a very different shape.