Abstract: Fusion in Space: Nuclear Astrophysics, Neutron Star Mergers, and Accretion Disks
In the extreme environments achievable in the core of a dying or dead star, nuclear reactions—both fusion and fission—are of fundamental importance. Fusion of elements lighter than iron and the fission of unstable heavy isotopes are both deep reservoirs of energy. Moreover, understanding the nuclear reactions occurring in space helps us answer questions about our own origins by providing insight into the formation of the material of which we are composed.
In this talk, I will describe one recent, exciting topic in nuclear astrophysics—a kilonova. In 2017, we observed the merger of two neutron stars—ultracompact cores of dead stars. After the merger, they probably eventually formed a torus of material orbiting around and accreting onto a central black hole. I present state-of-the-art numerical models of this “accretion disk” system and describe how neutron star merger disks contribute to observable effects and the total abundance of heavy elements in the universe.
1 Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM, USA
2 Center for Theoretical Astrophysics, Los Alamos National Laboratory, Los Alamos, NM, USA
3 CCS-2, Los Alamost National Laboratory, Los Alamos, NM, USA