David J. Hartley

Spin ∼60 ℏ in 156Dy: competition between collective and terminating structures at very high-spin

AbstractThe highest-spin discrete states x0e.I;60 and E ;30 MeV in normal deformed nuclei have been observed in the x rare-earth isotope Dy using the Sn S,4n reaction in conjunction with the GAMMASPHERE spectrometer. The 156 124 x0e 36 .positive parity yrast sequence appears to evolve smoothly from a prolate collective towards an oblate non-collectivex0e. x0e .shape, in contrast to the sudden shape change observed in the isotone 158 Er. Terminating states are identified in the negativeparity sequences at I p s52 y and 53 y and specific multi-particle-hole configurations are assigned by comparison withcranked Nilsson-Strutinsky calculations. An order of magnitude increase in the interaction strength between close lyinghigh-spin weakly collective structures is determined compared with that found in the lower-spin strongly collective domain.These results give valuable insight into the interplay between collective and terminating structures, and their competition foryrast status in the 40y60 spin range. q1998 Elsevier Science B.V. All rights reserved.

Rotational band structures in N = 89 153 Gd

The reactions

Exploring the I = 50-60 hbar domain: collective and terminating structures in 156Dy, 159Er and 160Er

{}^{152}mathrm{Sm}(ensuremath{alpha},3n)

Relative quadrupole deformations for structures in odd proton Pr nuclei near mass

at 37 MeV and

Highly deformed structures in the mass∼130 region and their relative quadrupole moments

{}^{124}mathrm{Sn}{(}^{36}mathrm{S},ensuremath{alpha}3n)

The A~130 Highly-Deformed Region: New Results and Global Differential Lifetime Measurements

at 165 MeV were used to produce high-spin states in the transitional rare-earth nucleus

Nuclear structure of neutron-rich 78 As

{}^{153}mathrm{Gd}.

Rotational bands in 170 Yb and 171 Yb and the projected shell model

Significant extensions in angular momentum and excitation energy with respect to earlier work were achieved and several new rotational sequences were observed. The rotational behavior of

High precision quadrupole moment measurements of states up to I = 20 ħ in the yrast band of 158 Er

{}^{153}mathrm{Gd}

Second proton and neutron alignments in the doubly-odd nuclei {sup 154,156}Tb

is described in terms of quasiparticle assignments and the observed alignment properties are analyzed within the framework of the cranked shell model. Detailed comparisons with other