STUDIES OF ALPHA PARTICLES FROM THE Li$sup 6$-Li$sup 6$ NUCLEAR REACTION

Journal Article · Thu Aug 15 04:00:00 EDT 1963 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.131.1701· OSTI ID:4697934

Kamegai, M

The reaction mechanism and the states in Be/sup 8/ in a Li/sup 6/induced reaction Li/sup 6/(Li/sup 6/, alpha )Be/sup 8/ yields 3 alpha were studied by a double coincidence experiment in which angles and energies of the two simultaneous alphas were recorded. The bombarding energy was 1.9 Mev. When the datu are transformed to the center-of-mass system, it is shown that a mechanism in which the entire available energy is divided equally between two alphas emitted 180 deg apart is some 23 times more probable than one in which one of the alphas recoils from Be/sup 8/ in its ground state. There are also satellite coincidence maxima at 169 deg and 192 deg . The pattern can be interpreted as due to a cluster reaction mechanism in which Li/sup 6/ combines with a deuteron cluster to produce a state of Be/sup 8/ at 20.95 plus or minus 0.3 Mev which is (Li/sup 6/ + d)-like. The pattern is fitted best, if a Breit-Wigner probability distribution for the excited Be/sup 8/ state is assumed, by a total width of 3.4 Mev. It is estimated that the alpha -decay width of this state is 260 plus or minus 90 kev. Such a mechanism has previously been suggested by Coste and Marquez, following ideas of Temmer. The angular distribution of the alpha group which leaves Be/sup 8/ in its ground state is nearly isotropic in the barycentric system. It seems that the reaction leading to the ground state of Be/sup 8/ proceeds through an intermediate compound nucleus, C/sup 12*/ absolute total cross section for an intermediate stage involving the ground state of Be/sup 8/ is 5.8 x 10/sup -29/ cm/sup 2/ for the 20.85 Mev state it is 13 x 10/sup -28/ cm/ sup 2/. (auth)

• Research Organization: Univ. of Chicago
• NSA Number: NSA-17-031517
• OSTI ID: 4697934
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 131; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALPHA DECAY
ALPHA PARTICLES
ANGULAR DISTRIBUTION
BERYLLIUM 8
BREIT-WIGNER FORMULA
CARBON 12
CLUSTER MODEL
COINCIDENCE METHODS
CONFIGURATION
CROSS SECTIONS
DEUTERONS
DISPERSION THEORY
DISTRIBUTION
ENERGY
ENERGY LEVELS
LITHIUM 7
NUCLEAR MODELS
NUCLEAR REACTIONS
PHYSICS
REACTION KINETICS
RECOILS
RECORDING SYSTEMS