Isospin properties of electric dipole excitations in 48Ca
  Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between 6.6 and 9.51 MeV provided strength distribution and parities, and an (\alpha,\alpha'\gamma) experiment at E_{\alpha}=136 MeV gave cross sections for an isoscalar probe. The unexpected difference observed in the dipole response is compared to calculations using the first-order random-phase approximation and points to an energy-dependent isospin character. A strong isoscalar state at 7.6 MeV was identified for the first time supporting a recent theoretical prediction. 
V. Derya, D. Savran, J. Endres, M.N. Harakeh, H. Hergert, J.H. Kelley,   P. Papakonstantinou, N. Pietralla, V.Yu. Ponomarev,...
nucl-ex nucl-th