Calculation of multichannel reactions in the four-nucleon system above breakup threshold

TL;DR

This paper solves exact four-body equations for neutron-3He and proton-3H scattering above the four-nucleon breakup threshold, providing detailed cross sections and spin observables that align well with experimental data.

Contribution

It presents a comprehensive calculation of multichannel reactions in the four-nucleon system using exact four-body equations and realistic interaction models, including effects of $ riangle$-isobar excitation.

Findings

Calculated cross sections and spin observables match experimental data reasonably well.

The approach includes realistic nucleon-nucleon interactions with effective many-nucleon forces.

The method provides detailed insights into elastic, transfer, charge-exchange, and breakup reactions.

Abstract

Exact four-body equations of Alt, Grassberger and Sandhas are solved for neutron-${}^3\mathrm{He}$ and proton-${}^3\mathrm{H}$ scattering in the energy regime above the four-nucleon breakup threshold. Cross sections and spin observables for elastic, transfer, charge-exchange, and breakup reactions are calculated using realistic nucleon-nucleon interaction models, including the one with effective many-nucleon forces due to explicit $\Delta$-isobar excitation. The experimental data are described reasonably well with only few exceptions such as vector analyzing powers.