Nuclear Seminar

The s process signature in SiC presolar grains: a constrain for stellar nucleosynthesis and nuclear astrophysics

Dr. Marco Pignatari
Keele University, U.K.

Monday, May 5, 2008   4:00 p.m.   NSH 124
(Refreshments served prior to seminar in NSH 124)

In the last years the analysis of the nucleosynthesis signature in pre-solar grains is the strongest constrain for stellar nucleosynthesis. Pre-solar silicon carbide grains (SiC) condensed in the envelope of ancient AGB stars or in the ejecta of supernovae, carrying the signature of the processes working in the parent stars. In particular, the analysis of the s-process elements provides useful information about the stellar environment conditions when the s-process was activated in stars. I discuss a few examples where SiC grain measurements are compared with stellar model yields, providing a useful tool to test the stellar models and the nuclear astrophysics network used in the calculations. Preliminary results of the new post-processing code PPN are presented.