Investigating Resonant State Modification with a Coulomb Trajectory Model

Unstable nuclei in isolation decay with well-defined energy distributions parameterized by their intrinsic energy and lifetime; resonant states are experimentally identified by examining relative energies between two or more daughter particles. When ejected from an excited parent, long-lived resonant states decay unperturbed while very short-lived states decay in the vicinity of the parent; this proximity introduces non-negligible Coulomb interactions which modify the observed energy. Previous work investigating resonant state modification has shown that the phenomenon can be reproduced qualitatively. Through the development of a C++/ROOT Coulomb trajectory model, we investigate the nature of these effects by examining simulated relative energy distributions of common short-lived ejectiles such as 8Be (2+) and 5Li (3/2-) emitted from excited heavy nuclei. Building upon previous work, this model implements nuclear surface stabilization as a function of inter-nuclear distance between the decay components in an attempt to more accurately replicate experimental results.