2N and 3N Systems in a Three Dimensional Formalism

We present an overview of our framework used to treat two- and three-nucleon (2N, 3N) systems employing three dimensional momentum eigenstates. Using a three dimensional formalism instead of the classical partial wave approach is an attractive alternative for a number of reasons, the most prominent being the very direct way of performing calculations. With the use of our tools it is possible to produce a working numerical realization of calculations in only a couple of steps from the fundamental (Schrödinger or Lippmann–Schwinger) equations. The FORTRAN implementations of the most complicated parts of the calculations are generated automatically by M a t h e m a t i c a ® software that was written in our group. Additionally, at higher energies, three dimensional calculations avoid problems arising from slow convergence of partial wave decomposition based techniques. Our approach utilizes a very general form of the 2N and 3N forces and has been successfully used to obtain results for the 2N transition operator as well as for the 2N and 3N bound states (Golak et al. in Phys Rev C 81:034006, 2010 ; Few-Body Syst 53:237, 2012a ; Few-Body Syst, 2012b ).