![This collision recorded by the UA1 experiment on 30 April 1983 is the first detection of a Z0 particle. (Image : CERN)](https://cern70.cern/wp-content/uploads/2023/12/8704168-A4-at-144-dpi.jpg)
On 25 January, CERN’s UA1 and UA2 experiments announce the discovery of the W boson, the particle that mediates the weak force, marking a significant milestone in particle physics. This discovery at the Super Proton Synchrotron (SPS) is followed a few months later by that of the Z boson, completing the experimental verification of the electroweak interaction theory.