Speaker
Dominique Meyer
(Argelander Institut fur Astronomie, Bonn)
Description
Observations of stellar wind bow shocks can be used to constrain stellar, circumstellar and interstellar medium (ISM) properties. This presentation aims at introducing a grid of two-dimensional hydrodynamical simulations of wind-ISM interaction of massive runaway stars. This explores the combined effects of space velocities (ranging from 20 to 70 km/s) and initial masses (ranging from 10 to 40 solar masses) of runaway stars on the structure of their bow shocks. The stellar evolution is followed from the main-sequence to the red supergiant phase. We included optically thin radiative cooling along with heating from H ionisation for models involving main-sequence stars, and from the Galactic UV background for models involving red supergiant stars in our treatment of the gas, together with electronic thermal conduction.
We classify our models of bow shocks in accordance with the density and temperature conditions prevailing in those structures, discriminating between adiabatic and radiative cases. We dwell upon the mixing process induced by thermal conduction, which transports dusty ISM material into the inner layers of the bow shocks and influencing their luminosity. Together with H emission maps of our models of bow shocks, we have derive constraints which may help to observe and characterised this kind of stars.
Author
Dominique Meyer
(Argelander Institut fur Astronomie, Bonn)