Eta Carinae is one of the most massive and luminous binary systems known. Due to their luminosity both stars posses powerful stellar winds. These winds collide and the combination of their strength... Show moreEta Carinae is one of the most massive and luminous binary systems known. Due to their luminosity both stars posses powerful stellar winds. These winds collide and the combination of their strength and the orbital motion determines the 3D structure of the gas. The interaction of the ionizing photons emitted by the stars with the gas is the topic of this thesis. We use the SimpleX algorithm for radiative transfer to post process hydrodynamic simulations of the wind interaction in Eta Carinae. We show that SimpleX is suitable to investigate the ionization structure of colliding wind binaries. Knowing where the gas is ionized allows us to identify the areas where observed emission and absorption lines might form. This has important implications for several properties of the system, such as the line of sight and the physical parameters of the stars, such as the temperature or mass-loss rate. We also printed 3D models of the interaction region of the two winds and investigated the usage of 3D interactive figures in scientific publications. These tools not only allow for better visualization and understanding of the system, but are also of great help when presenting complex simulation results to non experts Show less
The SimpleX radiative transfer method is based on the interpretation of photons as particles interacting on a natural scale: the local mean free path. In our method, light is transported along the... Show moreThe SimpleX radiative transfer method is based on the interpretation of photons as particles interacting on a natural scale: the local mean free path. In our method, light is transported along the lines of an unstructured Delaunay mesh that encodes this natural distance and represents the physical medium. The SimpleX method is fast, highly adaptive and its computational cost does not scale with the number of sources. It is therefore well-suited for cosmological applications where it is essential to cover many orders of magnitude in resolution and where millions of sources can exist within a single simulation. We describe the code, its recent developments and apply it to several relevant astrophysical problems. In particular, we perform radiative transfer calculations of cosmological reionization and of the wind-wind interaction region of the Eta Carinae binary system. Show less
