PSILOGO

Laboratory for Particle Physics (LTP)


LTP Colloquium

Origin of the elements beyond Fe in stellar explosions - a continuing challenge for astrophysics and nuclear physics

Thursday, May 8, 2014, 16:00
OSGA/E6

T Rauscher, U. of Hertfordshire

Abstract:
The origin of the intermediate and heavy elements beyond Fe has been a long-standing, important question in astronomy and astrophysics, which also impacts our understanding of galactic evolution and of the early universe. Production of isotopes of these elements requires extreme conditions only realized in explosive astrophysical sites. At least 3 nucleosynthesis processes are required which occur in a number of different sites, ranging from repeated explosions in outer shells of stars to supernova explosions. While some of these can be well understood in terms of model simulations, especially supernova explosion modelling still poses a considerable challenge. In consequence, the natural production site of about 50% of all heavier isotopes remains unknown. Central to the understanding of all the nucleosynthesis processes are predictions of nuclear reaction rates involving unstable nuclei, which takes current nuclear models to the limit. Investigations in astrophysical and nuclear models, together with various "observational" information (obtained from stellar spectra, meteoritic inclusions, and nuclear experiments) comprise the pieces which have to be put together to solve the puzzle of the origin of the intermediate and heavy natural nuclides. It is an excellent example for the multifaceted, interdisciplinary approaches required to understand nucleosynthesis. I will provide selected examples of the challenges faced with special emphasis on nuclear physics in supernova nucleosynthesis.