1. Evolution of the circumstellar medium around massive stars
Sabina-Mădălina Chiţă ,
Norbert Langer, Allard-Jan van Marle
Sterrenkundig Instituut Universiteit Utrecht

2. NGC 7635 (The Bubble Nebula)
stellar wind bubble
H II region (photoionized)
3 pc wide

3. H-R diagram for 12 M⊙ star Presupernova stage :
MS-> RSG-> BSG-> RSG
data credit :A.Heger, Los Alamos

4. Stellar wind mass-loss history
RSG-> BSG-> RSG
mass loss
velocity
photoionization

5. ZEUS -3D code hydrodynamical code: credit Stone & Norman (1992)
solves the Euler equations on a fixed grid
photoionization: credit García-Segura (1999)
rotation: wind compressed disk model: credit Cassinelli & Bjorkman (1992)

6. 1D simulation of MS end of MS stage photoionized region hot bubble
MS shell

7. 1D simulation of RSG MS -> RSG old MS shell
new MS shell(hot bubble shell)
no photo- ionization
RSG shell

8. 2D simulation of RSG-> BSG-> RSG

9. 2D simulation of pre-supernova
final stage: pre- supernova
RSG shell

10. 2D simulation
RSG shell
3 pc

11. Outlook
SN 1987 A
BSG progenitor of SN1987 A

12. Thank you !