The 152 GeV Candidate at the LHC

by Bruce Mellado Garcia (IHEP)

Friday 14 Nov 2025, 10:00 → 12:00 Asia/Shanghai

摘要：

The discovery of a Higgs boson at the LHC consistent with the predictions of the Standard Model (SM) marked a major milestone in particle physics. In this light, the search for new Higgs-like bosons remains at the forefront of efforts to explore physics beyond the SM.
Based on several features observed in the data collected during Run 1 of the LHC, a simplified model was proposed in which a heavy scalar, H, decays into a combination of the SM Higgs boson (h) and a new Higgs-like scalar, S. One implication of this model is the appearance of excesses in lepton production when the decay S →WW dominates. These excesses, referred to as the multi-lepton anomalies at the LHC, were subsequently identified. They include events with two or more leptons, missing transverse energy, and (b)-jets in the final state. In turn, based on the invariant mass of lepton pairs, the mass of the new scalar is predicted to be mS = 150 ±5 GeV.

The analysis of γγ, Zγ, and WW sideband spectra in Run 2 data confirms the presence of a resonance at mS = 152 ±1 GeV, with a global significance of 5.3σ. This represents the strongest excess observed at the LHC to date that is consistent with a narrow resonance beyond the SM. These findings strongly motivate further investigation at future high-precision facilities such as the CEPC.

个人简介：

Bruce Mellado, PhD (Columbia University), has held professorships in the United States, South Africa, and at the Institute of High Energy Physics of the Chinese Academy of Sciences. He has served in multiple leadership roles at the European Laboratory for Particle Physics (CERN). He was the Institutional Board Chair and now he is the Deputy Project Leader of the Tile Calorimeter of the ATLAS experiment. His work has been recognized with several prestigious awards, including the TW Kambule-NSTF Prize for Research (2021), the Vice-Chancellor’s Prize for Research (2022), and the ODESS2025 Prize from the Pierre Fabre Foundation in France (2025), among others. He is a Fellow of both the African Academy of Sciences and the Academy of Science of South Africa.

An expert on the Higgs boson, Prof. Mellado was a leading contributor to its discovery, which culminated in the 2013 Nobel Prize in Physics. His team pioneered the identification of multi-lepton anomalies at the Large Hadron Collider, leading to the prediction of a new Higgs boson with a mass of around 150 GeV.