Systematic investigation of the Pygmy Dipole Resonance near the magic N = 82 shell closure

The Pygmy Dipole Resonance is part of the electric dipole response of an atomic nucleus. There are still several open questions concerning, e.g., its structure. Systematic studies are crucial to improve the knowledge of this excitation mode. Such systematic studies have already been performed along the magic N = 82
isotonic chain using the Nuclear Resonance Fluorescence (NRF) technique, hinting to a trend of increasing strength with increasing N/Z ratio. Comparing these results to those from further NRF experiments on neighbouring non-magic isotopes and on 142Ce, a more fragmented strength distribution seems to occur.