Total cross section measurements of [sup 16]O+[sup 232]Th incomplete fusion followed by fission at 140 MeV

Journal Article · Sat Apr 01 04:00:00 EST 1995 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.51.1991· OSTI ID:6545629

Gavathas, E P; Frawley, A D; Kline, R C; Dennis, L C ^[1]

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1. Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

Total cross sections for incomplete fusion followed by fission have been measured for the reaction [sup 16]O+[sup 232]Th at 140 MeV. In-plane and out-of-plane measurements were made of cross sections for beamlike fragments in coincidence with fission fragments. The beamlike fragments were detected with a Bragg curve spectrometer which is position sensitive in the polar direction. The beamlike particles observed in coincidence with fission fragments were He, Li, Be, B, C, N, and O. One fission fragment from each reaction was detected by one of three surface barrier detectors using time of flight for particle identification. The measured cross section due to fission following incomplete fusion is 747[plus minus]112 mb, or 42% of the total fission cross section. The strongest incomplete fusion channels were the He and C channels. The average transferred angular momentum for each incomplete fusion channel was predicted using the [ital Q][sub opt] model of Wilczynski so that the [ital K] distribution could be estimated from the rotating liquid drop model. The experimental angular distributions were fitted using the saddle point transition state model, with the transferred angular momentum [ital J] and the dealignment factor [alpha][sub 0] as free parameters. The saddle-point transition state model is found to adequately describe the observed angular correlations for fission following incomplete fusion. The fitted parameter [ital J] showed systematic deviations from the [ital Q][sub opt] model predictions, suggesting that the average impact parameter is larger than expected for heavy projectile fragments.

• OSTI ID: 6545629
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Journal Name: Physical Review, C (Nuclear Physics); (United States) Vol. 51:4; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

663450* -- Heavy-Ion-Induced Reactions & Scattering-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALKALI METAL ISOTOPES
ALKALINE EARTH ISOTOPES
ANGULAR DISTRIBUTION
ANGULAR MOMENTUM
BERYLLIUM 9
BERYLLIUM ISOTOPES
BORON 11
BORON ISOTOPES
CARBON 12
CARBON ISOTOPES
CHARGED-PARTICLE REACTIONS
COINCIDENCE METHODS
COUNTING TECHNIQUES
CROSS SECTIONS
DISTRIBUTION
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FISSION FRAGMENTS
HEAVY ION REACTIONS
HELIUM 4
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
LITHIUM 6
LITHIUM ISOTOPES
NITROGEN 14
NITROGEN ISOTOPES
NUCLEAR FRAGMENTS
NUCLEAR REACTIONS
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
OXYGEN 16
OXYGEN 16 REACTIONS
OXYGEN ISOTOPES
STABLE ISOTOPES
TARGETS
THORIUM 232 TARGET
TIME-OF-FLIGHT METHOD
TOTAL CROSS SECTIONS