Beta decay of neutron-rich 118Ag and 120Ag isotopes

Abstract

b decays of on-line mass-separated neutron-rich 118Ag and 120Ag isotopes have been studied by using b-g and g-g coincidence spectroscopy. Extended decay schemes to the 118,120Cd daughter nuclei have been constructed. The three-phonon quintuplet in 118Cd is completed by including a new level at 2023.0 keV, which is tentatively assigned the spin and parity of 24 1 . The intruder band in 118Cd is proposed up to the 41 level at 2322.4 keV. The measured b-decay half-life for the high-spin isomer of 120Ag is 0.4060.03 s. Candidates for the three-phonon states, as well as the lowest members of the intruder band in 120Cd, are also presented. These data support the coexistence of quadrupole anharmonic vibration and proton particle-hole intruder excitations in 118,120Cd.