Spin distribution of the compound nucleus in heavy ion reactions at near-barrier energies

Journal Article · Wed May 01 04:00:00 EDT 1985 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.31.1752· OSTI ID:5885119

Gil, S; Vandenbosch, R; Lazzarini, A J; Lock, D; Ray, A

Gamma ray multiplicities and the (HI,xn) cross sections for the dominant reaction channel were measured at near-barrier bombarding energies for the systems ..cap alpha..+ /sup 154/Sm and /sup 12/C+ /sup 154/Sm. The mean value of the spin distribution of the compound nucleus was obtained for each of the systems studied. The results of these measurements together with the results of an earlier study on /sup 16/O+ /sup 154/Sm indicate that at bombarding energies near and below the Coulomb barrier the spin distributions of the compound nucleus are broader than the triangular distributions expected from a sharp cutoff model, these deviations being larger for the more massive projectiles. The different behavior of the three systems clearly indicates the importance of the centrifugal barrier penetrability in determining the spin distribution of the compound nucleus. The absolute values of the mean angular momentum can be accounted for if one also includes deformation effects. A one-dimensional barrier-penetration model including the effect of averaging over the orientation of the deformed target can account for the experimental results.

• Research Organization: University of Washington, Seattle, Washington 98195
• OSTI ID: 5885119
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 31:5; 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
ALPHA REACTIONS
ANGULAR DISTRIBUTION
ANGULAR MOMENTUM
CARBON 12 REACTIONS
CHARGED-PARTICLE REACTIONS
COMPOUND-NUCLEUS REACTIONS
CROSS SECTIONS
DEFORMED NUCLEI
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ENERGY
ENERGY RANGE
GAMMA RADIATION
HEAVY ION REACTIONS
IONIZING RADIATIONS
MEV RANGE
MEV RANGE 10-100
MULTIPLICITY
NUCLEAR REACTIONS
NUCLEI
PARTICLE PROPERTIES
RADIATIONS
SAMARIUM 154 TARGET
SPIN
TARGETS
THRESHOLD ENERGY