SOLITON SCATTERINGS IN SOME RELATIVISTIC MODELS IN (2+1) DIMENSIONS

The authors consider the O(3) sigma -model, modified by the addition of both a potential term and a Skyrme-like term. The instanton solutions in two Euclidean dimensions are viewed as static solutions in (2+1) dimensions. They study their stability and also look at their scattering behaviour. Most of the work is numerical, with the model being formulated in terms of a single complex field. They find that the inclusion of the additional terms stabilises the solitons. Their study of their scattering processes reveals that the force between them is repulsive. In low-energy scattering the solitons bounce back off each other, while at larger energies they scatter at right angles. The scattering is quasi-elastic and their shape is unchanged after collisions.