 |
Center for Nonlinear Studies |
R Coronae Borealis (RCB) stars are hydrogen deficient and highly variable objects with a rich and unusual emission-line spectrum. Current theories suggest that RCB stars are post-merger objects resulting from the collision of a Helium White Dwarf and a Carbon/Oxygen White Dwarf. This theory is supported by numerical stellar simulations which give similar surface abundances as reported from observations. Our group performed these simulations in MESA (Modules for Experiments in Stellar Astrophysics), a 1-dimensional stellar simulation program. One problem with this is a binary system is inherently a multi-dimensional system which requires a 3- dimensional hydrodynamics code to accurately simulate. However, because we want to simulate this object through thermal and nuclear timescales, it is not feasible to use a 3-dimensional code to simulate the entire life of the RCB star. Our goal is to simulate the merger event in a 3-dimensional AMR hydrodynamics code called OctoTiger and average the profile of the post-merger object over all angles for mapping into MESA in order to simulate the rest of the stars life. This simulation is also made more realistic through work with the Nucleosynthesis Grid (NuGrid) collaboration as this allows us to post-process our data with a significantly larger nuclear network to get a better idea of the stars composition profile and how it evolves.
Host: Wes Even