 In some instances, however, predictions based on this model underestimate the total amount of energy released in the form of gamma rays; that is, nuclei appear to have more than enough energy to eject neutrons, but decay by gamma emission instead.This discrepancy is found by the energy of a nuclear angular momentum, and documentation and calculation of "yrast" levels for a given system may be used for analyzing such a situation.The energy stored in the angular momentum of an atomic nucleus can also be responsible for the emission of larger-than-expected particles, such as alpha particles over single nucleons, because they can carry away angular momentum more effectively.