An R-matrix model for three-body final states is presented and applied to a recent measurement of the neutron energy spectrum from the T+T->2n+alpha reaction. The calculation includes the n-alpha and n-n interactions in the final state, angular momen
tum conservation, antisymmetrization, and the interference between different channels. A good fit to the measured spectrum is obtained, where clear evidence for the 5He ground state is observed. The model is also used to predict the alpha-particle spectrum from T+T as well as particle spectra from 3He+3He. The R-matrix approach presented here is very general, and can be adapted to a wide variety of problems with three-body final states.
A general framework for deconvoluting the effects of energy averaging on charged-particle reaction measurements is presented. There are many potentially correct approaches to the problem; the relative merits of some of are discussed. These deconvolut
ion methods are applied to recent 12C(alpha,gamma)16O measurements.
We review some aspects of R-matrix theory and its application to the semi-empirical analysis of nuclear reactions. Important applications for nuclear astrophysics and recent results for the ${}^{12}{rm C}(alpha,gamma){}^{16}{rm O}$ reaction are emphasized.
