Presenter(s): Carl Ranney − Physics
Faculty Mentor(s): James Imamura
Poster 36
Research Area: Physical Science
The purpose of this research is to determine the validity of the fission model of short orbital period binary star formation. The fission model describes the process in which a protostar with large angular velocities splits into two bodies in orbit around a common center of mass. The fission model is one of the three major models currently under investigation by the wider astrophysical community as possible sources for the formation of short orbital period binary star systems. While fission has not received much attention in the last two decades due to results found in large scale numerical simulations, the advances in computational power now available allow much more complex simulations that show promise in solving this problem. Rather than looking at single stars, we are simulating the evolution of a rotating protostar with a large circumstellar disk that is approaching a reverse Roche limit, where the mass of the disk starts to pull the protostar apart. By including this large disk in our calculations, we find that the prospects for fission is greatly enhanced. We are using the computer code Chymera in Aciss and Talapas, the University of Oregon high-performance computing clusters in our study to simulate the fluid dynamics of this system. Chymera includes many nonlinear instabilities which were not widely known or where undiscovered during the period when the last major simulations of the fission model were attempted. With the combination of these two factors, our research has provided valuable insight into previously unexplored aspects of the complex system.