2D simulations of LBV-like atmospheres and wind outflows
Pieter Schillemans
K.U. Leuven

S Doradus-like Luminous Blue Variables (LBVs) are a rare class of evolved massive stars. These stars are characterised by re-occuring yet unpredictable outbursts, where the LBV increases its optical brightness and decreases its effective temperature and as such moves across the HRD. In this eruptive-like phase, LBV mass-loss rates presumably can increase to 10^-3 solar masses per year or higher, which can heavily impact the further evolution of the star. Despite its importance in stellar evolution, the mechanisms controlling LBV eruptions, and more generally the behaviour of stars in this luminous and unstable region of the HRD, remain poorly understood. I will present initial 2D radiation-hydrodynamic simulations of LBV-like atmospheres and their outflows. These atmospheric models start off deep in the stellar envelope (~400kK), using static opacities, and go up to the line-driven outer wind. I will discuss the first results and implications of these models, which call into question if 1D radiative transfer and model atmosphere codes are really suitable to infer mass-loss rates and atmospheric parameters for stars in this parameter regime.

Date:	Jeudi, le 28 novembre 2024
Heure:	11:30
Lieu:	Pour tous
	En-ligne seulement