Speaker
Description
There is overwhelming evidence that new power sources and more complex geometries are strictly necessary for explaining the observed light curves of certain astrophysical transients, e.g. supernovae in the presence of surrounding medium. Numerical models are challenging due the need of performing radiation-hydrodynamic simulations across a wide dynamic range of both time and space, which typically implies an elevated computational cost. In this context, we have developed a new tool that solves the multi-dimensional radiation-hydrodynamic equations in spherical coordinates over a domain that is allowed to expand radially. The equations are solved using the operator-splitting technique in three steps: an explicit update using the Godunov method for the hydrodynamic hyperbolic equations, an explicit update to account for radiation sink/source terms, and an implicit update for radiation diffusion, emission, and absorption processes. We have shown that this approach is ideal for simulating astrophysical transients over ten orders of magnitude spatially and temporarily even if the sources lack of spherical symmetry . We present the implementation, results of our first application: wind-reprocessed transients, and also ongoing work simulating supernovae and tidal-disruption events. Part of the content is based on our published peer-reviewed article: Calderón D., Pejcha O., Duffell P. C., 2021, Monthly Notices of the Royal Astronomical Society, 507, 1092. doi:10.1093/mnras/stab2219
