Entry states in subbarrier fusion
Conference
·
OSTI ID:5957741
The cross section for fusion of heavy ions below the Coulomb barrier can be orders of magnitude larger than the predictions of models that are quite successful above the barrier. Recent studies of ..gamma..-ray multiplicity have shown that the average l of the partial waves participating in subbarrier fusion is much higher than expected. The discrepancies become larger as the mass asymmetry of the projectile and target decreases. We have used the Spin Spectrometer in coincidence with identified products from two reactions leading to the same compound nucleus, /sup 164/Yb, to study entry-state angular-momentum effects. The reactions were /sup 64/Ni + /sup 100/Mo and /sup 16/O + /sup 148/Sm; the conditions of bombardment are listed. The O + Sm energies were chosen to match two of the Ni + Mo compound-nucleus excitation energies. Exit channels were identified by known ..gamma..-ray lines from the residual nuclei observed in six Compton-suppressed Ge detectors which replaced a like number of pentagonal NaI units of the Spin Spectrometer. Recording of events was triggered by detection of a ''clean'' Ge pulse (i.e., no ..gamma.. ray detected in its surrounding Compton shield). 10 refs., 5 figs., 2 tabs.
- Research Organization:
- Oak Ridge National Lab., TN (USA); Washington Univ., St. Louis, MO (USA)
- DOE Contract Number:
- AC02-76ER04052; AC05-84OR21400
- OSTI ID:
- 5957741
- Report Number(s):
- CONF-860396-5; ON: DE86008888
- Country of Publication:
- United States
- Language:
- English
Similar Records
Spin distributions and decay of {sup 164}Yb* formed in nearly symmetric and asymmetric fusion reactions
Search for entrance channel effects in the decay of the [sup 164]Yb compound nucleus at [ital E][sup *][approx]54 MeV
Formation and decay of [sup 164]Yb[sup *] in near- and below-barrier fusion reactions
Journal Article
·
Wed Mar 31 23:00:00 EST 1993
· Bulletin of the American Physical Society
·
OSTI ID:243786
Search for entrance channel effects in the decay of the [sup 164]Yb compound nucleus at [ital E][sup *][approx]54 MeV
Journal Article
·
Tue Nov 30 23:00:00 EST 1993
· Physical Review, C (Nuclear Physics); (United States)
·
OSTI ID:5574517
Formation and decay of [sup 164]Yb[sup *] in near- and below-barrier fusion reactions
Journal Article
·
Tue Nov 30 23:00:00 EST 1993
· Physical Review, C (Nuclear Physics); (United States)
·
OSTI ID:5574505
Related Subjects
651725* -- Nuclear Properties & Reactions
A=90-149
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
COINCIDENCE METHODS
COMPOUND-NUCLEUS REACTIONS
COUNTING TECHNIQUES
CROSS SECTIONS
ENERGY RANGE
EVEN-EVEN NUCLEI
HEAVY ION FUSION REACTIONS
HEAVY ION REACTIONS
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOTOPES
MEV RANGE
MEV RANGE 10-100
MEV RANGE 100-1000
MOLYBDENUM 100 TARGET
NICKEL 64 REACTIONS
NUCLEAR REACTIONS
NUCLEI
OXYGEN 16 REACTIONS
RADIOISOTOPES
RARE EARTH ISOTOPES
RARE EARTH NUCLEI
SAMARIUM 148 TARGET
TARGETS
YTTERBIUM 164
YTTERBIUM ISOTOPES
A=90-149
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
COINCIDENCE METHODS
COMPOUND-NUCLEUS REACTIONS
COUNTING TECHNIQUES
CROSS SECTIONS
ENERGY RANGE
EVEN-EVEN NUCLEI
HEAVY ION FUSION REACTIONS
HEAVY ION REACTIONS
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOTOPES
MEV RANGE
MEV RANGE 10-100
MEV RANGE 100-1000
MOLYBDENUM 100 TARGET
NICKEL 64 REACTIONS
NUCLEAR REACTIONS
NUCLEI
OXYGEN 16 REACTIONS
RADIOISOTOPES
RARE EARTH ISOTOPES
RARE EARTH NUCLEI
SAMARIUM 148 TARGET
TARGETS
YTTERBIUM 164
YTTERBIUM ISOTOPES