While the origins of the light (hydrogen, helium) and intermediate mass (carbon through iron) elements found in our solar system are well understood, we still are not sure where roughly half of the elements heavier than iron were made. From the solar system abundance pattern of these nuclei, we can tell they were made in an extreme neutron-rich environment via rapid neutron capture, or r-process, nucleosynthesis. We understand the basics of how the r-process must proceed - heavy elements are built up through a sequence of neutron captures and beta decays involving thousands of nuclei far from stability. However, where in the galaxy the appropriate conditions occur is still not conclusively known. Here we will review the basic features of several potential r-process environments and describe how heavy element synthesis could proceed in each. Then we will discuss how current and next generation nuclear physics experiments can play a key role in solving this long-standing mystery.
Argonne Physics Division Seminar Schedule