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arXiv · 2309.17107

Three-pion scattering: From the chiral Lagrangian to the lattice

Abstract

In recent years, detailed studies of three-pion systems have become possible in lattice QCD. This has in turn led to interest in 3-to-3 scattering of pions in the chiral perturbation theory framework. In addition to being an interesting study of multi-meson dynamics in its own right, it provides a valuable handle on finite-volume effects and the pion mass dependence, thus complementing the lattice results. I present our derivation of the next-to-leading order amplitude for this process, as well as its conversion into the three-particle K-matrix, which enables direct comparison to the lattice. Our results significantly improve the agreement between theory and lattice, which was poor when only leading-order effects were taken into account.

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Jorge Baeza-Ballesteros, Johan Bijnens, Tomáš Husek, Fernando Romero-López, Stephen R. Sharpe, Mattias Sjö. 2023-09-29. Three-pion scattering: From the chiral Lagrangian to the lattice. https://doi.org/10.1016/j.nuclphysbps.2023.09.023

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