Neutron emission in /sup 12/C+/sup 158/Gd and /sup 13/C+/sup 157/Gd reactions between 8 and 12 MeV/nucleon

Journal Article · Sun Nov 01 04:00:00 EST 1981 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.24.2048· OSTI ID:6066941

Gavron, G; Beene, J R; Ferguson, R L; Obenshain, F E; Plasil, F; Young, G R; Petitt, G A; Young, K G; Jaeaeskelaeinen, M; Sarantites, D G; Maguire, C F

Neutron spectra in coincidence with evaporation residues and with projectilelike fragments emitted in inelastic scattering reactions have been measured at several bombarding energies for /sup 12/C- and /sup 13/C-induced reactions leading to the same compound nucleus /sup 170/Yb. In the fusion reactions, a nonequilibrium component was observed in the neutron spectra at all beam energies. This component is forward peaked and is associated with a high temperature. The spectra can be parametrized by assuming the nonequilibrium part to result from a hot region (Tapprox.4 MeV) emitting neutrons isotropically and moving with a velocity of approximately 1 cm/ns. This apparent velocity decreases with decreasing beam velocity. Comparisons are made with predictions based on the generalized critical angular momentum model of incomplete fusion of Siwek-Wilczynska et al. No significant difference has been observed between nonequilibrium neutron emission from /sup 12/C- and /sup 13/C-induced reactions. Neutron emission associated with inelastic scattering reactions cannot be described by simple statistical evaporation from two fragments of equal temperature. Effects which may give rise to the observed energy and angular distributions of neutrons in coincidence with inelastic products are discussed.

• Research Organization: Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830
• OSTI ID: 6066941
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 24:5; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651825* -- Nuclear Properties & Reactions
A=150-189
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR DISTRIBUTION
ANGULAR MOMENTUM
CARBON 12 REACTIONS
CARBON 13 REACTIONS
CHARGED-PARTICLE REACTIONS
COINCIDENCE SPECTROMETRY
COMPOUND-NUCLEUS REACTIONS
DATA
DISTRIBUTION
ENERGY RANGE
EVAPORATION MODEL
EXPERIMENTAL DATA
FRAGMENTATION
GADOLINIUM 157 TARGET
GADOLINIUM 158 TARGET
HEAVY ION REACTIONS
INELASTIC SCATTERING
INFORMATION
MATHEMATICAL MODELS
MEV RANGE
MEV RANGE 100-1000
NEUTRON SPECTRA
NUCLEAR MODELS
NUCLEAR REACTIONS
NUMERICAL DATA
PRECOMPOUND-NUCLEUS EMISSION
SCATTERING
SPECTRA
TARGETS