Test of Three-Body Separable Pole Expansions at Negative and Positive Energies

摘要

We compare the performance of separable pole expansions for the three-body amplitude in reproducing three-body data at both negative and positive energies. In addition to the Generalized Unitary Pole Expansion and the Energy Dependent Pole Expansion, we present results for two new expansions. As benchmarks for our calculations, we use the three-boson results of Aaron, Amado, and Yam. At positive energies, we calculate phase shifts and inelasticities. At negative energies, we give off-shell scattering amplitudes and investigate how well the expansions are capable of generating the second bound state of the three-boson problem, if the first is put explicitly into the expansions. In general, we find that the results get better the more energy dependence is explicitly contained in the expansion functions. The relevance of these findings for four-body calculations, which employ separable three-body input, is discussed briefly. (ERA citation 08:024749)