Testing the Physics of Nuclear Isomers

摘要

For much of the past century, physicists have searched for methods to control the release of energy stored in an atom's nucleus. Nuclear fission reactors have been one successful approach, but finding other methods to capitalize on this potential energy source have been elusive. One possible source being explored is nuclear isomers. An isomer is a long-lived excited state of an atom's nucleus—a state in which decay back to the nuclear ground state is inhibited. The nucleus of an isomer thus holds an enormous amount of energy. If scientists could develop a method to release that energy instantaneously in a gamma-ray burst, rather than slowly over time, they could use it in a nuclear battery. Research in the late 1990s indicated that scientists were closer to developing such a method—using x rays to trigger the release of energy from the nuclear isomer hafnium-178m (~(178m)Hf). To further investigate these claims, the Department of Energy (DOE) funded a collaborative project involving Lawrence Livermore, Los Alamos, and Argonne national laboratories that was designed to reproduce those earlier results.