Hirschi, R and Frischknecht, U and Thielemann, F-K and Pignatari, M and Bennett, M and Diehl, S and Fryer, CL and Herwig, F and Hungerford, A and Magkotsios, G and Rockefeller, G and Timmes, FX and Young, P (2008) NuGrid: s process in massive stars. In: 10th Symposium on Nuclei in the Cosmos, 27 Jul - 1 Aug 2008, Mackinac Island, Michigan, USA.
0811.4654v1.pdf - Published Version
Available under License Creative Commons Attribution Non-commercial Share Alike.
Download (135kB) | Preview
The s-process production in massive stars at very low metallicities is expected to be negligible due to the low abundance of the neutron source 22Ne, to primary neutron poisons and decreasing iron seed abundances. However, recent models of massive stars including the effects of rotation show that a strong production of 22Ne is possible in the helium core, as a consequence of the primary nitrogen production (observed in halo metal poor stars). Using the PPN post-processing code, we studied the impact of this primary 22Ne on the s process. We find a large production of s elements between strontium and barium, starting with the amount of primary 22Ne predicted by stellar models. There are several key reaction rate uncertainties influencing the s-process efficiency. Among them, 17O(alpha,gamma) may play a crucial role strongly influencing the s process efficiency, or it may play a negligible role, according to the rate used in the calculations. We also report on the development of a new parallel (MPI) post-processing code (MPPNP) designed to follow the complete nucleosynthesis in stars on highly resolved grids. We present here the first post-processing run from the ZAMS up to the end of helium burning for a 15 solar mass model.
|Item Type:||Conference or Workshop Item (Paper)|
|Subjects:||Q Science > QB Astronomy
Q Science > QC Physics
|Divisions:||Faculty of Natural Sciences > School of Physical and Geographical Sciences|
|Date Deposited:||15 Jul 2015 14:06|
|Last Modified:||15 Jul 2015 14:06|
Actions (login required)