Nuclear γ-ray coincidence experiments in high-intensity photon beams

High energy photons are an important experimental probe in nuclear structure physics and have been used in the past decades for the investigation of low-spin structures of atomic nuclei. A topic of particular interest in recent years in this field is the Pygmy Dipole Resonance, an electric dipole (E1) excitation mode located well below the E1 giant resonance. Even though the PDR has been investigated systematically using high energy photons its decay properties were not accessible up to now. New experiments using the method of γ-γ coincidences will allow to study this important quantity in detail.