ACP Seminar (Astronomy - Cosmology - Particle Physics)

Speaker: Shinya Wanajo (National Astronomical Observatory)
Title: Nucleosynthesis beyond iron: supernovae vs. neutron star mergers
Date (JST): Tue, Aug 27, 2013, 15:30 - 16:30
Place: Seminar Room A
Abstract: Origin of species heavier than iron, in particular of r-process nuclei, remains a long-standing puzzle. I will present our latest result of nucleosynthesis studies based on multi-dimensional hydrodynamical simulations of core-collapse supernovae (with the MPA group) and neutron star mergers (preliminary, with the Kyoto group). Our result suggests that light trans-iron elements from Zn to Zr, as well as some important species such as the neutron-rich isotope 48Ca and the radionuclide 60Fe, can be produced in core-collapse supernovae. It appears, however, that the main r-process species (A > 120) cannot be synthesized in supernovae. I will show that the full-range of r-process species can be obtained in the dynamical ejecta from neutron star mergers and in the subsequent neutrino-driven winds. A connection to the recent finding of a possible "kilo nova" (r-process-powered electro-magnetic transient) will also discussed.