Speaker
Description
Multi-boson processes are among the most sensitive tests of the Standard Model. Theoretical predictions for these interactions are extremely precise, so even small discrepancies could point to new physics phenomena. Triboson processes are the rarest of this kind, offering unique sensitivity to probe quartic boson couplings and complementarity with Higgs physics and searches beyond the Standard Model. In this talk, we will report the first evidence of simultaneous production of two Z bosons together with a photon (ZZγ) for the first time at the LHC. The measurement is performed using the full Run-2 dataset, recorded from 2015 to 2018, of proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 140 fb^{−1}. Eight events are selected, with a background estimate of 0.92 ± 0.15. This results in an observed (expected) significance of the ZZγ final state of 4.4 (4.4). The study extends the LHC’s repertoire of multi-boson studies and provides a complementary test to those already observed.
