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arXiv · 2512.04336

LHC Shines on Positivity

Abstract

We show that hadron colliders have an excellent reach for positivity tests on a class of diphoton operators. Due to the helicity selection rules, the relevant dimension-6 operators either do not contribute or are highly constrained by other experimental observables. We show, for the first time, that the LHC can probe the positivity of the dimension-8 operators involving colored particles. The kinematic differential distributions of the diphoton final states are exploited to perform the $\chi^2$ analysis. Through a global fit, the effective scale for these operators can be inclusively probed up to around 2 TeV at HL-LHC and over 5 TeV at future 100 TeV FCC-hh at 95% C.L., providing a powerful test of the positivity bounds up to multi-TeV scale.

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Zhen Liu, Kun-Feng Lyu, Tong Arthur Wu. 2025-12-03. LHC Shines on Positivity. https://arxiv.org/abs/2512.04336

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