Our approach to the inclusion of star formation produces galaxies that are similar to those observed, despite the limited amount of physics that has been put in. Effects that should be incorporated in the future are mass loss from stars in the form of supernovae and stellar winds, metallicity effects, ionization balance and a finite opacity.
Strong points of the recipe are its simplicity, the fact that it based on global properties (such as the Jeans criterion and radiative heating), the weak dependence on the model parameters and the strong dependence on the physical ingredients.
Our simulations produce self-regulated star formation due to thermal equilibrium of the ISM. They provide plausible explanations for flocculent spiral structure and truncation of galactic disks.
It is important to note that the TREESPH code does not require any special geometry. By its nature it is very well suited for three-dimensional problems such as interacting galaxies. We intend to run simulations of star formation in interacting starburst galaxies, simultaneously solving the complicated stellar radiation field, the highly inhomogeneous gas density and the dynamical heating. If we discard the dynamical heating the SFR should be approximately linearly correlated with the gas density in the starburst regions, since stellar heat input from outside is unimportant. Simulations of this kind will be presented in a future paper.
© European Southern Observatory (ESO) 1997
Online publication: April 28, 1998