Giant eruptions in massive stars and their effect on the stellar structure

The evolution and characteristics of massive stars are significantly influenced by mass loss and mass accretion, through stellar winds, accretion disks, and binary interactions. These mechanisms have a notable impact on the stellar envelope as they approach the main sequence, leading to substantial changes in their structure. I use numerical simulations to investigate how massive stars react to eruptive mass loss and accretion of material and analyze the resulting changes in their evolutionary track, energy transport, and internal structure. In the talk I will present simulation results that show how mass loss leads to a decrease in luminosity in the evolutionary track, causing the star to become hotter and contract. This is not a monotonic process and includes several stages. I will also discuss simulations of accretion that lead to an increase in luminosity and radial expansion of the star toward cooler temperatures. A discrepancy exists between high and low accretion rates: for low accretion rates the star remains hot, whereas higher accretion rates lead to the cooling of the star. For each simulation, I monitor the star’s progression into the recovery phase as well.
I will show a comparison of normal evolution without mass loss and accretion to evolution where either process takes place.