Astroparticle Physics Seminar

Jonathan Mackey, Computer simulations of stellar-wind bubbles, the pre-supernova nebula of SN 1987A and particle acceleration


Wind bubbles around massive stars have complex structure, especially during late stages of evolution where stellar properties can change dramatically over short timescales.  In many (but not all) cases multidimensional simulations and synthetic observations are required to gain an understanding of observational data.  I will describe the latest resease our simulation software PION, designed for 2D/3D MHD simulation of wind bubbles from evolving massive stars, and will show some first results from this newly upgraded capability.  We then apply this to investigate the three rings of the pre-supernova nebula around SN 1987A.  Both single-star and binary evolutionary models have been proposed to explain the progenitor and its nebula, and here we explore radiation-MHD models for the single-star case.  There are challenges to simultaneously reproducing the three rings and the photoionized gas required by thermal X-ray emission, but overall the results are promising.  This model informed 1D hydrodynamic and particle-acceleration calculations of the supernova expansion using RATPaC, allowing us to predict high-energy radiation from the supernova as it evolves.