Scattering of a spin-1/2 particle off a spin-0 target in a simple three-dimensional basis

Scattering of a spin-1/2 particle off a spin-0 target is formulated based on a simple three-dimensional momentum-spin basis. The azimuthal behaviour of both the potential and the T-matrix elements leads to a set of integral equations for the T-matrix elements in two variables only, namely the momentum's magnitude and the scattering angle. Some symmetry relations for the potential and the T-matrix elements reduce the number of the integral equations to be solved by a factor of one half. A complete list of the spin observables in terms of the two-dimensional T-matrix elements is presented.