Dipole response of 238U to polarized photons below the neutron separation energy

1) dipole strengths in nuclei[1]. Observation of dipole states are important because theycharacterize the various collective and single-particle nuclearexcitation modes, in particular, the scissors mode, the spin-flip mode, and the pygmy dipole resonance. These differentexcitation modes are prominent in various regions below ornear the neutron separation energy and represent importantnuclear structure phenomena. For