A new model of the structure of spiral galaxies based on propagating star formation - II. The effect of a spiral density wave
We have constructed a new model for galactic structure based on the principles of propagating star formation. Unlike earlier simulations using this mechanism, it represents the galactic molecular clouds as distinct entities which move, interacting with one another through collisions, in a smooth gravitational field. This allows us to superimpose on the propagating star formation a potential which represents the underlying dynamics of the stellar population, and to include more realistic physics describing the interstellar medium. In this paper we investigate in more detail the effects of one such potential, namely a spiral density wave, both on the resulting structures and on the star formation rate.