content_image/374442.jpg content_image/374440.jpg content_image/374439.jpg content_image/374441.jpg
multiplicities. Here, ε$_{0}$ is the excitation energy of the decaying nucleus, B$_{0}$ its binding energy and E$_{c}$$_{0}$ is a term associated with the Wigner-Seitz correction to the Coulomb energy of the system. V$_{n}$ is the volume in which the momentum states are normalized and is usually defined as [8] 

<img src='content_image/374442.jpg'>

where V$_{0}$ is the ground state volume of the decaying nucleus and the expansion factor χ is usually taken to be χ = 1 . For the fragments, B$_{j}$ is the binding energy of fragment j and g$_{j}$ is its spin multiplicity, while the E$_{cj}$ represent the remaining Wigner-Seitz corrections to the Coulomb energy, taken to be 

Conservation of nucleon number and charge requires that 

<img src='content_image/374440.jpg'>

<img src='content_image/374439.jpg'>

where Z$_{j}$ and A$_{j}$ are the charge and mass number, respectively, of fragment j . The FBM assumes that the fragments are emitted in their ground states or in (almost) particle-stable excited states. 

As the total excitation energy is increased, other particle-unstable excited states that are long-lived in comparison to the initial decaying nucleus could also be included and can make significant contributions to the phase space integral[27]. These can be incorporated compactly using the densities of excited states of the fragments. Such an extension of the Fermi breakup integral takes the form 

<img src='content_image/374441.jpg'>

where ε$_{j}$ is the excitation energy of fragment j , ω$_{j}$ ( ε$_{j}$ ) its density of states and B$_{j}$ is now its ground-state binding energy. Note that this expression does not contain the fragment spin multiplicities, g$_{j}$ , which are now assumed to be incorporated in the density of states. For a particle with no excited states, we have ω$_{j}$ ( ε$_{j}$ ) = g$_{j}$δ ( ε$_{j}$ ) . 

