Interacting binary galaxies. II. Matching models to observations

This paper presents an efficient numerical simulation algorithm called the multiple three-body algorithm for the study of interacting elliptical galaxies. The highlights of the algorithm are given, and the galaxy model and how the perturber scales with the primary galaxy are described. The methods by which the model galaxies can be flattened and by which they can receive varying degrees of internal rotation rate are shown. Model observations that can be measured on the sky of a variably oriented observer are described, discussing examples of various observables. The free parameters of the problem are identified, while the procedure is outlined by which a search of that parameter space is begun for a simulation that matches all of the observations available for a given pair of galaxies. The uniqueness of the solutions is discussed in the context of a particular two-dimensional cut through the multidimensional model parameter space. 32 references