Bethe Prize: Nuclear Astrophysics and its Role in Astrophysical Transients

Astrophysical transients are a primary source of the injection of heavy elements into the Milky Way from alpha group and iron peak elements to neutron capture elements. Measuring the properties (mass and distribution) of these elements in transients both allow us to understand the chemical evolution of the Galaxy and probe the nature of the transient engine and its progenitor. Astronomy databases of transient light curves and spectra are rapidly expanding and this observational data has the potential to place limits on the elements injected into the Milky Way by transients. But inferring abundances from these atomic spectra is difficult, requiring detailed atomic physics and radiation hydrodynamic calculations incorporating out-of-equilibrium effects. Observations of gamma-rays from the decay of radioactive nuclei have much more straightforward interpretations, minimizing the modeling uncertainties, allowing us to directly determine the injection of key isotopes into the Milky Way. But to tie these observations to the nature of the supernova engine and its underlying physics does require the inclusion of a broad range of physics from hydrodynamics to nuclear cross-sections. The physics community has developed a range of experiments and studies that can and should be leveraged to build next generation models of these transients. Here I will review the current state of the field, discussing the importance of a broad range of physics fields to our studies of astrophysical transients.