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Three-Nucleon Force and the $Δ$-Mechanism for Pion Production and Pion Absorption

M. T. Peña·P. U. Sauer·A. Stadler·G. Kortemeyer
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Abstract

The description of the three-nucleon system in terms of nucleon and $Δ$ degrees of freedom is extended to allow for explicit pion production (absorption) from single dynamic $Δ$ de-excitation (excitation) processes. This mechanism yields an energy dependent effective three-body hamiltonean. The Faddeev equations for the trinucleon bound state are solved with a force model that has already been tested in the two-nucleon system above pion-production threshold. The binding energy and other bound state properties are calculated. The contribution to the effective three-nucleon force arising from the pionic degrees of freedom is evaluated. The validity of previous coupled-channel calculations with explicit but stable $Δ$ isobar components in the wavefunction is studied.

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M. T. Peña, P. U. Sauer, A. Stadler, G. Kortemeyer. 1993-05-20. Three-Nucleon Force and the $Δ$-Mechanism for Pion Production and Pion Absorption. https://doi.org/10.1103/physrevc.48.2208

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