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arXiv · 2203.04693

PION: Simulations of Wind-Blown Nebulae

Jonathan Mackey·Samuel Green·Maria Moutzouri·Thomas J. Haworth·Robert D. Kavanagh·Maggie Celeste·Robert Brose·Davit Zargaryan·Ciarán O'Rourke
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Abstract

We present an overview of PION, an open-source software project for solving radiation-magnetohydrodynamics equations on a nested grid, aimed at modelling asymmetric nebulae around massive stars. A new implementation of hybrid OpenMP/MPI parallel algorithms is briefly introduced, and improved scaling is demonstrated compared with the current release version. Three-dimensional simulations of an expanding nebula around a Wolf-Rayet star are then presented and analysed, similar to previous 2D simulations in the literature. The evolution of the emission measure of the gas and the X-ray surface brightness are calculated as a function of time, and some qualitative comparison with observations is made.

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Jonathan Mackey, Samuel Green, Maria Moutzouri, Thomas J. Haworth, Robert D. Kavanagh, Maggie Celeste, Robert Brose, Davit Zargaryan, Ciarán O'Rourke. 2022-03-09. PION: Simulations of Wind-Blown Nebulae. https://doi.org/10.1017/s1743921322001399

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