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arXiv · 2505.22190

Convergence of the $ppp$ correlation function within the hyperspherical adiabatic basis

Abstract

The computation of the three-particle correlation function involving three hadrons started just recently after the first publications of ALICE measurements. Key elements to be considered are the correct description of the asymptotics, antisymmetrization issues and, in most cases, the treatment of the Coulomb interaction. In the case of the $ppp$ correlation function, a first analysis was done where the hyperspherical adiabatic method was used to determine the $ppp$ wave function at different energies. Although the asymptotic behavior, antisymmetrization issues and the treatment of the Coulomb interaction were discussed in detail, the convergence properties of the adiabatic basis were studied at low energies around the formation of the correlation peak determined mainly by the $J^\pi=1/2^-$ and $3/2^-$ three-body states. Since many and very precise data have been taken or are planned to be measured at energies beyond the peak, we present an analysis of the convergence characteristics of the basis as the energy of the process increases. We show that in order to describe correctly the correlation tail it is necessary to consider three-body states up to $J^\pi=21/2^-$ whereas higher states can be considered as free. Once those states are incorporated solving the associate dynamical equations, the agreement with the experimental data is found to be excellent.

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E. Garrido, A. Kievsky, R. Del Grande, L. Serksnyte, M. Viviani, L. E. Marcucci. 2025-05-28. Convergence of the $ppp$ correlation function within the hyperspherical adiabatic basis. https://doi.org/10.1016/j.physletb.2025.139731

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