Star cluster ecology. I. A cluster core with encounters between single stars

Star clusters with a high central density contain an ecological network of evolving binaries, affected by interactions with passing stars, while in turn affecting the energy budget of the cluster as a whole by giving off binding energy. This is the first paper in a series aimed at providing the tools for increasingly realistic simulations of these ecological networks. Here we model the core of a globular star cluster. The two main approximations are: a density of stars constant in space and time, and a purely single star population in which collisions between the evolving stars are modeled. In future papers in this series, we will relax these crude approximations. Here, however, they serve to set the stage before proceeding to the additional complexity of binary star interactions, in paper II, and background dynamical evolution, in later papers.