J. F. Sharpey-Schafer

Evidence for Octupole Correlations in Multiple Chiral Doublet Bands

Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive- and negative-parity bands have been identified in ^{78}Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei.

Highly excited Delta I=1 structures in 193Hg

Highly excited states in the nucleus 193Hg have been investigated by in-beam gamma -ray spectroscopic techniques using the EUROGAM array. The reaction 150Nd(48Ca,5n) at a beam energy of 213 MeV was used to populate states of 193Hg. The level scheme has been considerably extended (up to 10.7 MeV) and enriched from earlier studies. Two new structures of competing dipole and quadrupole transitions were observed. Experimental B(M1)/B(E2) ratios were determined for the two structures and compared with theoretical estimates. They were also compared with similar structures in the neighbouring Hg and Pb nuclei.

Observation of γ vibrations and alignments built on non-ground-state configurations in Dy156

The exact nature of the lowest Kπ=2+ rotational bands in all deformed nuclei remains obscure. Traditionally they are assumed to be collective vibrations of the nuclear shape in the γ degree of freedom perpendicular to the nuclear symmetry axis. Very few such γ bands have been traced past the usual backbending rotational alignments of high-j nucleons. We have investigated the structure of positive-parity bands in the N=90 nucleus Dy156, using the Nd148(C12,4n)Dy156 reaction at 65 MeV, observing the resulting γ-ray transitions with the Gammasphere array. The even- and odd-spin members of the Kπ=2+γ band are observed up to 32+ and 31+, respectively. This rotational band faithfully tracks the ground-state configuration to the highest spins. The members of a possible γ vibration built on the aligned yrast S band are observed up to spins 28+ and 27+. An even-spin positive-parity band, observed up to spin 24+, is a candidate for an aligned S band built on the seniority-zero configuration of the 0+2 state at 676 keV. The crossing of this band with the 0+2 band is at ℏωc=0.28(1)MeV and is consistent with the configuration of the 0+2 band not producing any blocking of the monopole pairing.

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)

Two-Particle Separation Energies in the Superdeformed Well

at 37 MeV and

A study of fusion - fission at Z = 107

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

DSAM lifetime measurements for the chiral bands in 194Tl

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

Spectroscopy of 161Hf from low to high spin

{}^{153}mathrm{Gd}.

Possible chiral bands in 194Tl

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