Quadrupole Phonons in the Cadmium Isotopes

A key question concerning the spherical-vibrator attributes of states in Cadmium isotopes is addressed by means of a boson Hamiltonian encompassing U(5) partial dynamical symmetry. The U(5) symmetry is preserved in a segment of the spectrum and is broken in particular non-yrast states, and the resulting mixing with the intruder states is small. The vibrational character is thus maintained in the majority of low-lying normal states, as observed in $^{110}$Cd.
Comment: 6 pages, 1 figure, 2 tables, Physical Review C (Rapid Communication). arXiv admin note: text overlap with arXiv:1810.05917