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arXiv:2604.16268

Experimental prospects for quantum decoherence measurements at colliders

Rafael Aoude, José M. Camacho, Valentin Durupt, Guillermo García-Mir, Fabio Maltoni B, María Moreno Llácer, Leonardo Satrioni, Kazuki Sakurai, M. Vos

Published Apr 17, 2026• 0 citations
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Abstract

We study the impact of radiation on quantum systems defined by the spins of elementary fermion-antifermion pairs produced at colliders. We present predictions for several processes, showing that energetic final-state radiation can induce decoherence and significantly reduce the entanglement of quantum systems formed by elementary fermion pairs. We investigate the feasibility of observing this effect experimentally in exclusive samples with energetic radiation. A statistically significant signal can be obtained with current data in associated $pp \rightarrow t\bar{t}(g)$ production at the LHC and in $e^+e^- \rightarrow τ^{+}τ^{-}(γ)$ production at Belle 2. Future electron-positron colliders operated at the $Z$ pole or well above the $t\bar{t}$ production threshold will extend these prospects further.

DOI
10.48550/arxiv.2604.16268

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