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ΛΛ¯ spin correlations in high-energy collisions from quantum channels: An open quantum system view of hadronization

João Barata1,*, Iván Cuntín1,2,†, Enrique Rico1,3,4,5,‡, and Bin Wu2,§

  • *Contact author: joao.lourenco.henriques.barata@cern.ch
  • †Contact author: ivan.cuntin.broullon@usc.es
  • ‡Contact author: enrique.rico.ortega@cern.ch
  • §Contact author: b.wu@cern.ch
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Phys. Rev. D 114, 076021 – Published 14 October, 2026

DOI: https://doi.org/10.1103/rxp7-gdng

Abstract

We construct a quantum information-centered approach to describe the experimentally observed behavior of hyperon spin-pair correlations in high-energy collider experiments. The evolution of the spin density matrix of the hyperon pair is treated in the language of quantum channels, accounting both for the spin dynamics in C2⊗C2 and for the pair’s angular separation ΔR. We show that the experimental data are consistent with an evolution under a two-qubit depolarizing channel, from which a Lindblad master equation is derived. This provides an open quantum system picture of spin dynamics during the hadronization transition, which is not naturally captured by other quantum channels, and we discuss its microscopic origins. These results show that quantum information science can offer new insights into confinement dynamics beyond the classification of entanglement in the final particle states.

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Phys. Rev. D 114, 076021– Published 14 October, 2026
  • Received 8 July 2026
  • Accepted 29 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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