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The decay properties of the Pygmy Dipole Resonance (PDR) have been investigated in the semi-magic N=82 nucleus ��������Ce using a novel combination of nuclear resonance fluorescence and �������coincidence techniques. Branching ratios for transitions to low-lying excited states are determined in a direct and model-independent way both for individual excited states and for excitation energy intervals. Comparison of the experimental results to microscopic calculations in the quasi-particle phonon model exhibits an excellent agreement, supporting the observation that the Pygmy Dipole Resonance couples to the ground state as well as to low-lying excited states. A 10% mixing of the PDR and the [2+1��PDR]is extracted.

The existing Nuclear Resonance Fluorescence (NRF) setup at the HI��S facility at the Triangle Universities Nuclear Laboratory at Duke University has been extended in order to perform ��-�� coincidence experiments. The new setup combines large volume LaBr3:Ce detectors and high resolution HPGe detectors in a very close geometry to offer high efficiency, high energy resolution as well as high count rate capabilities at the same time. The combination of a highly efficient ��-ray spectroscopy setup with the mono-energetic high-intensity photon beam of HI��S provides a worldwide unique experimental facility to investigate the ��-decay pattern of dipole excitations in atomic nuclei. The performance of the new setup has been assessed by studying the nucleus \sulfur at 8.125 MeV beam energy. The ��-decay branching ratio from the $1^+$ level at 8125.4 keV to the first excited $2^+$ state was determined to 15.7(3)%., 9 pages, 11 figures