Spin-trap isomers in deformed, odd-odd nuclei in the light rare-earth region near N = 98

Masses of neutron-rich, odd-odd Pm, Eu, and Tb nuclei near N = 98 were measured using the Canadian Penning Trap mass spectrometer at the Californium Rare Isotope Breeder Upgrade (CARIBU) facility. High -resolution mass measurements yielded the discovery of spin-trap isomers at N = 97 in Tb-162, and in the N = 99 isotones of Pm-160 and Tb-164. Furthermore, no evidence of long-lived isomers were observed at N = 95 in Eu-158, at N = 97 in Pm-158, nor at N = 101 in Eu-164 and Tb-166. These experimental observations are compared to results from multiquasiparticle blocking calculations.