München 2019 – wissenschaftliches Programm
HK 36.4: Vortrag
Mittwoch, 20. März 2019, 15:00–15:15, HS 14
Investigation of the Pygmy Dipole Resonance in 120,124Sn using the combined γ-ray and particle spectrometers CAGRA and Grand Raiden — •M. Weinert for the CAGRA collaboration — University of Cologne, Institute for Nuclear Physics, Germany
During the CAGRA+GR campaign in 2016, the magnetic spectrometer Grand Raiden at the RCNP in Osaka (Japan) has been used in combination with the clover-detector array CAGRA to study the excitation and decay behavior of the Pygmy Dipole Resonance (PDR) in various nuclei. Placing the Grand Raiden spectrometer at very forward angles, dipole excitations can be investigated with high sensitivity, while the CAGRA spectrometer observes the corresponding γ-decays with high efficiency. These types of experiments have already shown that the observed electric dipole response of atomic nuclei strongly depends on the excitation mechanism. A splitting of the states in the PDR region into at least two groups of states with different underlying isospin character has already been observed in other nuclei [1-3]. This contribution will
present first results from the measurements of 120Sn(α,α’γ)@130MeV
and 124Sn(p,p’γ)@80MeV from the CAGRA+GR campaign. A comparison of results from different experiments using complementary probes on these two nuclei will be given and possible evidence for an isospin splitting in 120Sn will be discussed.
Supported by DGF (ZI 510/7-1 and SFB 1245).
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