Radiative pion capture in 2H, 3He and 3H

TL;DR

This paper provides the first realistic predictions for radiative pion capture rates in light nuclei using advanced nuclear potentials and consistent treatment of nuclear states, including final state interactions.

Contribution

It introduces a comprehensive calculation of pion capture rates in light nuclei with consistent nuclear state treatment and final state interactions, improving upon previous models.

Findings

Predictions for differential and total capture rates are provided.

Results are compared with older theories and experimental data.

The study emphasizes the importance of final state interactions in accurate modeling.

Abstract

The $\pi^- + {^2{\rm H}} \rightarrow \gamma + n + n$, $\pi^- + {^3{\rm He}} \rightarrow \gamma + {^3{\rm H}}$, $\pi^- + {^3{\rm He}} \rightarrow \gamma + n + d$, $\pi^- + {^3{\rm He}} \rightarrow \gamma + n + n + p$ and $\pi^- + {^3{\rm H}} \rightarrow \gamma + n + n + n$ capture reactions are studied with the AV18 two-nucleon potential and the Urbana~IX three-nucleon potential. We provide for the first time realistic predictions for the differential and total capture rates for all these processes, treating consistently the initial and final nuclear states. Our results are based on the single nucleon Kroll-Ruderman-type transition operator and concentrate on the full treatment of the nuclear final state interactions. They are compared with older theoretical predictions and experimental data.