Kenneth M. Nollett, Physics Division, Argonne National Laboratory
Nuclear Physics in the pp Chain, r-Process, and x-Process
Physics Division Colloquium - 12 May 2006

More than 99 percent of the nuclei in nature have atomic masses less than thirteen. The history of nuclear abundances in the universe began with quark confinement into free neutrons and protons a tiny fraction of a second after the big bang. Within fifteen minutes, all of these nucleons had either gathered into alpha particles, remained as free protons, or been included in trace amounts of other light nuclides. The subsequent history of nuclei mostly involves stars condensing from the interstellar medium, producing sufficient temperature and density for nuclear reactions through gravitational contraction, and on occasion expelling the resulting products into the surrounding medium. Because the primordial nuclear processing produced only light nuclei, which still consitute most of the nuclei in nature, and because some environments dissociate nuclei back into free nucleons and alpha particles, many aspects of astrophysics depend on the physics of light nuclei. I will present a survey of the astrophysics of the light nuclei, its connection with the production of much larger nuclei, and its relation to the physical properties of the nuclei themselves. I will conclude with some prospects for tying up loose ends in this story, and for improving our quantitative knowledge of it through the application of ab initio nuclear theory.

ANL Physics Division Colloquium Schedule