Characterization of isomers of the nucleus154Pm

Consideration of the expected two-quasiparticle structures and their estimated band head energies, and the selection rules for beta transition rates for the¹⁵⁴Nd →¹⁵⁴Pm →¹⁵⁴Sm decays are used to deduce the configurations for the isomers and the low-spin structures in the neutron rich doubly odd nucleus ₆₁ ¹⁵⁴ Pm₉₃. The 2.68 m high spin isomer and the 1.73 m low spin isomer are respectively assigned the spin-parity 4⁺ and 1⁺ with the configuration {p:5/2⁻ [532↑] +n:3/2⁻ [521↑]} with the 2.68 m isomer lying lower in energy, and thus forming the¹⁵⁴Pm ground state. Two-quasiparticle character of the beta-connected states in¹⁵⁴Nd decay and¹⁵⁴Pm decay is discussed.