$R$-matrix description of particle energy spectra produced by low-energy $^{3}\mathrm{H}+^{3}\mathrm{H}$ reactions

$R$ -matrix description of particle energy spectra produced by low-energy ${}^{3}H + {}^{3}H$ reactions

C. R. Brune, J. A. Caggiano, D. B. Sayre, A. D. Bacher, G. M. Hale, and M. W. Paris

Phys. Rev. C 92, 014003 – Published 20 July 2015

Abstract

An $R$ -matrix model for three-body final states is presented and applied to a recent measurement of the neutron energy spectrum from the ${}^{3}H + {}^{3}H \to 2 n + α$ reaction. The calculation includes the $n α$ and $n n$ interactions in the final state, angular momentum conservation, antisymmetrization, and the interference between different channels. A good fit to the measured spectrum is obtained, where clear evidence for the $^{5} He$ ground state is observed. The model is also used to predict the $α$ -particle spectrum from ${}^{3}H + {}^{3}H$ as well as particle spectra from ${}^{3}{He} + {}^{3}{He}$ . The $R$ -matrix approach presented here is very general and can be adapted to a wide variety of problems with three-body final states.