Sum rules for dipole transitions in finite systems and the giant dipole resonance in nuclei
Tolokonnikov S. V., Fayans S. A.
An expression for the average energy of dipole photoabsorption is derived in the self-consistent theory of finite Fermi systems. This expression gives a correct description of both the position of the giant dipole resonance in nuclei (even the lightest) and the splitting of this resonance by static deformation. The approach developed here can be generalized in a natural way to other systems. In particular, it gives the average frequency of dipole transitions in an atom and in small metal particles.