PHYS-F-421

Nucleosynthesis

S. Goriely



Content

One of the major issues in modern astrophysics concerns the analysis and understanding of the present composition of the Universe and its various constituting objects. Nucleosynthesis models aim to explain the origin of the different nuclei observed in nature by identifying the possible processes able to synthesize them.

The composition of the various constituents of the Universe at the galactic and stellar scales has evolved since the Big Bang. Though the origin of most of the nuclides lighter than iron through the various hydrostatic and explosive burning stages in stars is now quite well understood, the synthesis of the heavy elements (i.e. heavier than iron) remains obscure in many respects. The major mechanisms called for to explain the production of the heavy nuclei are the slow neutron-capture process (or s-process) occurring during specific hydrostatic stellar burning phases, the rapid neutron-capture process (or r-process) believed to develop during the explosion of a star as a type II supernova or during the merging of two compact objects, and the photodisintegration process (or p-process) taking place in the high-temperature environment of type-Ia or type-II supernovae. The stellar nucleosynthesis requires a detailed knowledge not only of the astrophysical sites and physical conditions in which the processes take place, but also the nuclear structure and interaction properties for all the nuclei involved.

These lectures describe our present understanding of the stellar nucleosynthesis processes as well as the many experimental and theoretical efforts devoted to determine the related nuclear physics inputs of relevance. These include nuclear structure as well as decay and reaction properties of relevance in astrophysical environments. The specificity of such properties in a high-temperature astrophysical plasma will be emphasized. The lectures also describe the particular links developed between nuclear physics and astrophysics.



Some reference textbooks or reviews

Slides

(access restricted. To get access, please contact S. Goriely at sgoriely@astro.ulb.ac.be):

Additional papers for ULB students