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arXiv · 2507.05334

Searching for top-philic heavy resonances in boosted four-top final states

Abstract

New heavy resonances with sizeable couplings to top quarks can be probed through searches for beyond-the-Standard-Model effects in four-top production at the LHC. In this work, we present the first next-to-leading-order QCD predictions for the full on-shell and off-shell production of four-top events via new electroweak singlet states, along with dedicated analysis strategies based on the reconstruction and tagging of all final-state top quarks. We develop a detector-level simulation incorporating recent advances in top-tagging and boosted object reconstruction. Moreover, we demonstrate that searches at LHC Run 3 and high-luminosity phase in the zero-lepton, one-lepton and same-sign di-lepton channels can improve the sensitivity to the new physics cross sections by up to two orders of magnitude. In particular, colour-octet resonances with masses up to 2-2.5 TeV and colour-singlet states with masses up to 1-1.5 TeV are within reach for coupling values in the 0.1-1 range.

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Luc Darmé, Benjamin Fuks, Hao-Lin Li, Matteo Maltoni, Julien Touchèque. 2025-11-07. Searching for top-philic heavy resonances in boosted four-top final states. https://doi.org/10.1007/jhep11(2025)091

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