Interference effects in gg → H → Zγ beyond leading order Buccioni, Federico Devoto, Federica Djouadi, Abdelhak Ellis, John Quevillon, Jérémie Tancredi, Lorenzo The ATLAS and CMS collaborations at the LHC have recently announced evidence for the rare Higgs boson decay into a Z boson and a photon. We analyze the interference between the process gg→H→Zγ induced by loops of heavy particles, which is by far the dominant contribution to the signal, and the continuum gg→Zγ QCD background process mediated by light quark loops. This interference modifies the event yield, the resonance line-shape and the apparent mass of the Higgs boson. We calculate the radiative corrections to this interference beyond the leading-order approximation in perturbative QCD and find that, while differing numerically from the corresponding effects on the more studied gg→γγ signal, they are generally rather small. As such, they do not impact significantly the interpretation of the present measurements of the H→Zγ decay mode. 2024-09-11T08:54:23Z 2024-09-11T08:54:23Z 2024-03-26 journal article F. Buccioni, F. Devoto, A. Djouadi et al. B 851 (2024) 138596. [https://doi.org/10.1016/j.physletb.2024.138596] https://hdl.handle.net/10481/94334 10.1016/j.physletb.2024.138596 eng info:eu-repo/grantAgreement/ERC/H2020/949279 info:eu-repo/grantAgreement/ERC/H2020/804394 http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Elsevier