3D hydrodynamic simulations and nucleosynthesis of the i-process

Falk Herwig

University of Victoria

Highly non-solar, anomalous abundance distributions can be found in numerous astrophysical observations, such as H-deficient post-AGB stars, C-enhanced metal-poor stars and pre-solar grains extracted from meteorites. These abundance signatures provide a window into individual nuclear production sites that create the elements. The above examples all provide insight into the intermediate neutron-capture process that occurs in the convective-reactive environment of proton-rich material that is ingested into C12-rich convective He-shell burning. New large-scale, 3-D simulations of the turbulent entrainment and energetic nuclear feedback processes of H-ingestion reveal a previously unknown global oscillation, and demonstrate that traditional stellar evolution simulations are breaking down in this regime. Preliminary i-process abundance predictions show a surprising agreement with the previously poorly explained CEMP-s+r stars, indicating that this exotic neutron-capture process may play an important role in the early universe.

Date:	Thursday, 13 March 2014
Time:	11:30
Where:	Université de Montréal
	Pavillon Roger-Gaudry, local D-460
Contact:	Patrick Dufour