Physicists detect rare three-boson collision at world's most powerful particle accelerator
Researchers at CERN have observed the first evidence of three W and Z bosons produced simultaneously in proton collisions, a finding that validates fundamental physics models and demonstrates the LHC's ability to probe increasingly rare interactions. The result strengthens confidence in our understanding of particle behavior at extreme energies, critical for developing next-generation physics experiments and technologies.
Originaltitel: Measurement of <em>WWZ</em> and <em>ZH</em> Production Cross Sections at √s=13 and 13.6 TeV
<p>A measurement is presented of the cross section in proton-proton collisions for the production of two 𝑊 bosons and one 𝑍 boson. It is based on data recorded by the CMS experiment at the CERN LHC at center-of-mass energies √𝑠 =13 and 13.6 TeV, corresponding to an integrated luminosity of 200 fb−1. Events with four charged leptons (electrons or muons) in the final state are selected. Both nonresonant 𝑊𝑊𝑍 production and 𝑍𝐻 production, with the Higgs boson decaying into two 𝑊 bosons, are reported. For the first time, the two processes are measured separately in a simultaneous fit. Combining the two modes, signal strengths relative to the standard model (SM) predictions of 0.75+0.34−0.29 and 1.74+0.71−0.60 are measured for √𝑠 =13 and 13.6 TeV, respectively. The observed (expected) significance for the triboson signal is 3.8 (2.5) standard deviations for √𝑠=13.6 TeV, thus providing the first evidence for triboson production at this center-of-mass energy. Combining the two modes and the two center-of-mass energies, the inclusive signal strength relative to the SM prediction is measured to be 1.03+0.31−0.28, with an observed (expected) significance of 4.5 (5.0) standard deviations.</p>