Using fusion-evaporation reactions, a gas-filled recoil separator, and recoil-electron and recoil-electron-α tagging techniques, a new isomeric 1 2 201 At is identified, and an earlier reported corresponding state [T 1/2 = 273( 9) ms] in 199 At is confirmed. The 1 2 + state is suggested to originate from an intruder π (s 1/2 ) −1 configuration. In addition, nuclear structure of states below and above this 1 2 + state are studied in both nuclei. The isomer decays through a cascade of an E3 transition followed by a mixed M1/E2 transition to the 9 2 − ground state, and it is interpreted to be fed from nearly spherical 3 2 + and 5 2 + states originating from π (d 3/2 ) −1 and π (d 5/2 ) −1 configurations, respectively.

Gamma rays from excited states feeding a proton-emitting isomeric-state in 151 Lu have been observed for the first time. Comparison with state-of-the-art nonadiabatic quasiparticle calculations indicates an oblately deformed, 3/2 + proton-emitting state with a quadrupole deformation of β 2 = −0.11. The calculations suggest an increase in quadrupole deformation, to β 2 = −0.18, with increasing spin which is understood in terms of the mixing of Nilsson states at the Fermi surface. It is also shown that the proton decay half-life is consistent with that from a 3/2 + state with a quadrupole deformation of β 2 = −0.12.

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The level structure of 136 Nd has been investigated using the 100 Mo(40 Ar, 4n) reaction and the JUROGAM II+RITU+GREAT setup. The level scheme has been extended significantly. Many new bands have been identified both at low and high spin, among which are five nearly degenerate bands interpreted as chiral partners. Excitation energies, spins, and parities of the previously known bands are revised and firmly established, and some previously known bands have been revised. Configurations are assigned to the observed bands based on cranked Nilsson-Strutinsky calculations. The band structure of 136 Nd is now clarified and the various types of single-particle and collective excitations are well understood.