In-beam gamma-ray spectroscopy of states in /sup 197/Au and /sup 199/Au populated by the (t,2n) reaction

Thesis/Dissertation · Fri Jan 01 00:00:00 EST 1982

OSTI ID:6244415

Nail, T W

In order to study high-spin states in beta-stable and neutron-rich nuclei, in-beam gamma-ray spectroscopy was performed following triton-induced reactions on heavy nuclei. Initial studies on isotopically pure targets of /sup 208/Pb confirm that the dominate reaction for 10 to 16 MeV tritons is compared nucleus formation, followed by emission of two neutrons. The (t,2n) reaction was found to populate low-spin states as well as high-spin states, and to sufficiently align the high-spin states so that information on transition multipolarities can be obtained from gamma-ray angular distribution measurements. Preliminary experiments on /sup 232/Th show that for compound nuclei produced by triton bombardment of actinide targets, decay by neutron emission competes favorable with fission, so that conversion electron spectroscopy following (t,xn) reactions may be useful for studying actinide nuclei. Triton bombardment of isotopically pure /sup 196/Pt and /sup 198/Pt targets was used to study /sup 197/Au and /sup 199/Au, produced by the (t,2n) reaction. Excitation function, pulsed beam, and gamma-gamma coincidence experiments were performed on both targets, and gamma-ray angular distributions were measured in /sup 199/Au. Level schemes constructed from this data show that the systematic trends observed in the lighter odd-mass gold nuclei continue in /sup 197/Au, but deviations in these trends occur in /sup 199/Au. A 6 +- 2 ns isomer seen in /sup 197/Au is believed to be a 2-1/2+, three particle state. The theory which best explains the results of these experiments is the cluster-vibration model, as only this model correctly predicts the large level density of negative-parity states found at excitation energies of 1 to 2 MeV.

• Research Organization: Florida State Univ., Tallahassee (USA)
• OSTI ID: 6244415
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
GOLD 197
HIGH SPIN STATES
GOLD 199
ANGULAR DISTRIBUTION
COINCIDENCE METHODS
ENERGY LEVELS
EXCITATION FUNCTIONS
EXPERIMENTAL DATA
GAMMA SPECTRA
PLATINUM 196 TARGET
PLATINUM 198 TARGET
STRIPPING
TRITON REACTIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
COUNTING TECHNIQUES
CROSS SECTIONS
DATA
DAYS LIVING RADIOISOTOPES
DIRECT REACTIONS
DISTRIBUTION
FUNCTIONS
GOLD ISOTOPES
HEAVY NUCLEI
INFORMATION
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
NUCLEAR REACTIONS
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
SPECTRA
STABLE ISOTOPES
TARGETS
TRANSFER REACTIONS
651923* - Nuclear Properties & Reactions
A=190-219
Experimental- Energy Levels & Transitions- (-1987)