Excited structures in the proton-rich nucleus Dy-140 have been established following the decay of an 8(-) isomer. The excitation energy of the isomer is established to be 2.16 MeV with a half-life of 7.3 +/- 1.5 mus. The isomer decays into the yrast line at the 8 state, revealing a rotational band with a deduced deformation of beta(2) = 0.24(3). The isotope Dy-140 is the daughter of the deformed proton emitter Ho-141. The new information obtained here supports the role of deformation in proton emission and the previous assignments of single-particle configurations to the two proton emitting states in Ho-141. In addition, the reduced hindrance factor measured for the isomer is consistent with the trend observed in the N = 74 isotones. (C) 2002 Elsevier Science B.V. All rights reserved. References: 29
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