This award will support a detailed theoretical study of the mergers of dead solar-type stars. Such mergers have recently been proposed as an important channel for the production of supernovae explosions of the Ia type, which are the most important probes of the expansion of the universe over cosmic time. The research will use the CASTRO hydrodynamics code, and will model what happens when two white dwarfs come into contact during the merger process. The simulations will include a nuclear reaction network to determine whether it is possible for an explosion to take place at the time of the merger. The mergers will be modeled in the orbital (corotating) reference frame will minimize the numerical error, maintaining angular momentum conservation throughout coalescence. The simulation approach will be validated through rigorous testing that will demonstrate the ability of the algorithm to maintain stable Newtonian orbits.
The award will also support the training of students and early-career scientists in computational astrophysics. Codes from this project will be widely distributed to the community. The project is also expected to have a scientific impact by improving the understanding of supernova progenitors.
