Abstract
The vibrational model is extended by introducing isospin-dependent collective coordinates, permitting a description out-of-phase neutron-proton vibrations coupled by a density-dependent symmetry energy. The restoring force is calculated microscopically using the wavefunctions of a Woods-Saxon potential and the coupling with three-phonon states is taken into account. The model is able to describe the available experimental data (energies and multipole mixing ratios) on low-lying 2+ states, which were observed recently in nuclei near the shell closures (124Te, 140Ba, 142Ce and 144Nd), supporting the identification of these states as isovector quadrupole vibrations and predicting such states in 126-130Te.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
