ABSTRACT: Thermal pulsation is a complicated mixing event in AGB stars which involves interaction between several layers of the stellar interior, and which occurs on very short timescales compared to a star's evolutionary timescale. The temporal constraint makes these events difficult to resolve in a 1D stellar evolution codes, and instead they are typically studied in isolation through 3D smoothed-particle hydrodynamical simulations. However, in their 2015 instrument paper, Paxton et al. demonstrated that the 1D MESA (Modules for Experiments in Stellar Astrophysics) stellar evolution code could produce robust interior profiles of thermally pulsating AGB stars.
 

Following work done this year involving MESA models of massive stars (Ohlmann et al. 2017, Tashibu et al 2017), I have collaborated at the South African Astronomical Observatory to develop a software suite called “MESA2GADGET” in conjunction with Dr. Shazrene Mohamed. The result of the project is a Python-based toolkit for automating the projection of 1D stellar density profiles to 3D particle distributions for use in smoothed-particle hydrodynamics simulations. The package facilitates the conversion of 1D models of the interior structures of stars during exotic and time-sensitive evolutionary phases to initial conditions in 3D codes, and establishes an accessible foundation for prescribing empirically informed, rather than ad-hoc, evolutionary initial conditions for high resolution stellar simulations.
 

Because MESA allows the user to extract structural data at any evolutionary point, MESA2GADGET can also be used to provide powerful boundary conditions for 3D codes intending to model many other short-timescale mixing events, thus yielding broad scientific potential.