1994/06/14 by J. Christopher Mihos, Chris Mihos, Lars Hernquist +2
Engineering · Physics and Astronomy · #Astrophysics and Star Formation Studies #Fluid Dynamics Simulations and Interactions #Fluid Dynamics and Heat Transfer #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9406044
16 pages, uuencoded compressed postscript, accepted to the Astrophysical Journal. 13 postscript figures available upon request from [email protected]
arxiv created 1994/06/14 · arxiv updated 2009/12/01
We have incorporated star formation algorithms into a hybrid N-body/smoothed particle hydrodynamics code (TREESPH) in order to describe the star forming properties of disk galaxies over timescales of a few billion years. The models employ a Schmidt law of index n∼ 1.5 to calculate star formation rates, and explicitly include the energy and metallicity feedback into the ISM. Modeling the newly formed stellar population is achieved through the use of hybrid SPH/young star particles which gradually convert from gaseous to collisionless particles, avoiding the computational difficulties involved in creating new particles. The models are shown to reproduce well the star forming properties of disk galaxies, such as the morphology, rate of star formation, and evolution of the global star formation rate and disk gas content. As an example of the technique, we model an encounter between a disk galaxy and a small companion which gives rise to a ring galaxy reminiscent of the Cartwheel (AM 0035-35). The primary galaxy in this encounter experiences two phases of star forming activity: an initial period during the expansion of the ring, and a delayed phase as shocked material in the ring falls back into the central regions.