Stability of Kink Defects in a Deformed O(3) Linear Sigma Model
  We identify the kinks of a deformed O(3) linear Sigma model as the solutions of a set of first-order systems of equations; the above model is a generalization of the MSTB model with a three-component scalar field. Taking into account certain kink energy sum rules we show that the variety of kinks has the structure of a moduli space that can be compactified in a fairly natural way. The generic kinks, however, are unstable and Morse Theory provides the framework for the analysis of kink stability. 
A. Alonso Izquierdo (U. Salamanca), M.A. Gonzalez Leon (U. Salamanca)   and J. Mateos Guilarte (U. Salamanca)