The Role of the Isospin 3/2 Component in Elastic Neutron-Deuteron Scattering and in the Deuteron Breakup Reaction

H Witała ,R Skibiński,J Golak ,K Topolnicki ,H Kamada

doi:10.1142/s2010194518600509

Abstract

We discuss the importance of the three-nucleon isospin [Formula: see text] component in elastic neutron-deuteron scattering and in the deuteron breakup reaction. The contribution of this amplitude originates from charge-independence breaking of the nucleon-nucleon potential. We study the magnitude of that contribution to the elastic scattering and breakup observables, taking the Av18 nucleon-nucleon potential alone or combined with the Urbana IX three-nucleon force as well as the locally regularized chiral N4LO nucleon-nucleon potential alone or supplemented by the chiral N2LO three-nucleon force. We find that the isospin [Formula: see text] component is important for the breakup reaction and the proper treatment of charge-independence breaking in this case requires the inclusion of the [Formula: see text] state with isospin [Formula: see text]. For neutron-deuteron elastic scattering the [Formula: see text] contributions are insignificant and charge-independence breaking can be accounted for by neglecting [Formula: see text] component and using the effective t-matrix generated with the so-called [Formula: see text] rule.

Highlights

Charge-independence breaking (CIB) is well established in the two-nucleon (2N) system as evidenced e.g. by the values of the 1S0 scattering lengths, different for the neutron-proton, proton-proton, and neutron-neutron systems
Summary We investigated the importance of the scattering amplitude components with the total 3N isospin T = 3/2 in elastic nd scattering and in the deuteron breakup reaction
The inclusion of these components is required to account for CIB effects of the NN interaction

Summary

Introduction

Charge-independence breaking (CIB) is well established in the two-nucleon (2N) system as evidenced e.g. by the values of the 1S0 scattering lengths, different for the neutron-proton (np), proton-proton (pp) (with the Coulomb force subtracted), and neutron-neutron (nn) systems. The detailed treatment of the 3N system with CIB NN forces in the case of distinguishable or identical particles was formulated and described in.[3] To investigate the role of the amplitude with the total three-nucleon (3N) isospin T = 3/2 in elastic neutron-deuteron (nd) scattering and in the deuteron breakup reaction and to check if conclusions depend on the employed dynamics we performed calculations of these processes using two different dynamical inputs.

Results

Conclusion