Rotational bands in sup 176 Re and IBA calculations for odd-odd Re isotopes

Miscellaneous · Sun Jan 01 00:00:00 EST 1989

OSTI ID:5712561

Chou, W

Rotational bands in odd-odd {sup 176}Re have been studied via the heavy-ion reactions, {sup 159}Tb({sup 22}Ne,5n{gamma}) {sup 176}Re at MSU NSCL and {sup 165}Ho({sup 16}O,5n{gamma}) {sup 76}Re at SUNY Stony Brook, using in-beam {gamma}-ray spectroscopic techniques. Ge detectors, with anti-Compton shields, were used to take singles, coincidence, delayed-coincidence, and angular-correlation spectra. Two rotational bands have been characterized. One of the bands is the so-called doubly-decoupled band with {Delta}I = 2 E2 intra-band transitions. This band shows backbending at a crossing frequency ({approx} 0.29 MeV) close to that of even-even W but lower than that of {sup 177}Re. This suggests that the effects of the odd neutron and odd proton on the crossing frequency seem to cancel each other out in this particular case. The observation of this band supports the mechanism of heavy-ion compound-nucleus reactions forming particle states highly-aligned with rotation, with the subsequent {gamma}-ray cascades feeding down through similar states. The other band is a regular rotational band connected by {Delta}I = 1 transitions. No linking transitions between these two bands have been identified; therefore, spin could not be assigned uniquely. In general the results agree with some previous studies, but the delayed-coincidence results showed the existence of meta-stable states, which were not mentioned. IBA calculations have proven to be able to give an accurate description of the properties of low-lying collective levels in even-even and odd-mass nuclei. The author has extended this model to odd-odd nuclei, applied to the Re isotopes.

• Research Organization: Michigan State Univ., East Lansing, MI (USA)
• OSTI ID: 5712561
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
RHENIUM 176
ROTATIONAL STATES
COMPARATIVE EVALUATIONS
COMPOUND-NUCLEUS REACTIONS
EXPERIMENTAL DATA
GAMMA RADIATION
GAMMA SPECTROSCOPY
GE SEMICONDUCTOR DETECTORS
HEAVY ION REACTIONS
HOLMIUM 165 TARGET
NEON 22 REACTIONS
NEUTRONS
NUCLEAR MODELS
ODD-ODD NUCLEI
OXYGEN 16 REACTIONS
ROTATION
TERBIUM 159 TARGET
BARYONS
CHARGED-PARTICLE REACTIONS
DATA
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY LEVELS
EXCITED STATES
FERMIONS
HADRONS
INFORMATION
INTERMEDIATE MASS NUCLEI
IONIZING RADIATIONS
ISOTOPES
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
MOTION
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
NUMERICAL DATA
RADIATION DETECTORS
RADIATIONS
RHENIUM ISOTOPES
SEMICONDUCTOR DETECTORS
SPECTROSCOPY
TARGETS
651820* - Nuclear Properties & Reactions
A=150-189
Experimental