Molecular interpretation of the oscillations of the fusion excitation function for the. cap alpha. +/sup 40/Ca system

Journal Article · Wed Oct 01 00:00:00 EDT 1986 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.34.1248· OSTI ID:5143070

Michel, F; Reidemeister, G; Ohkubo, S

The oscillations observed in the experimental ..cap alpha..+ /sup 40/Ca fusion excitation function between E/sub ..cap alpha../ -- 10 and 27 MeV are described within the frame of the optical model. Use is made of an existing optical potential giving a precise description of the elastic scattering data for E/sub ..cap alpha../>24 MeV on a broad angular range, which is extrapolated to lower incident energies. A correct description of elastic scattering experimental excitation functions between E/sub ..cap alpha../ -- 12 and 18 MeV, as well as of the fusion excitation function, is achieved by using different imaginary geometries for both processes. The oscillations appearing in the calculated fusion excitation function are due to maxima in the even-l transmission coefficients, for l ranging from 6 to 12; these maxima correspond to shape resonances in the underlying potential, which are associated with states belonging to an excited positive parity band with N -- 14 in the ..cap alpha..+ /sup 40/Ca system. The same potential predicts an N -- 12 positive parity band of states whose energies are in good agreement with the /sup 44/Ti experimental ground state band. It is shown that the correct reproduction of the spacing between the fusion oscillations achieved here results from the use of a deep real potential, which automatically yields a decoupling between positive and negative parity bands.

• Research Organization: Faculte des Sciences, Universite de l'Etat, B-7000 Mons, Belgium
• OSTI ID: 5143070
• Journal Information: Phys. Rev. C; (United States), Vol. 34:4
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ALPHA REACTIONS
CAPTURE
ELASTIC SCATTERING
CALCIUM 40 TARGET
TITANIUM 44
ENERGY LEVELS
ANGULAR DISTRIBUTION
COULOMB FIELD
CROSS SECTIONS
EXCITATION FUNCTIONS
EXPERIMENTAL DATA
MEV RANGE 10-100
OPTICAL MODELS
PARITY
SPIN
ANGULAR MOMENTUM
BETA DECAY RADIOISOTOPES
CHARGED-PARTICLE REACTIONS
DATA
DISTRIBUTION
ELECTRIC FIELDS
ELECTRON CAPTURE RADIOISOTOPES
ENERGY RANGE
EVEN-EVEN NUCLEI
FUNCTIONS
INFORMATION
INTERMEDIATE MASS NUCLEI
ISOTOPES
MEV RANGE
NUCLEAR REACTIONS
NUCLEI
NUMERICAL DATA
PARTICLE PROPERTIES
RADIOISOTOPES
SCATTERING
TARGETS
TITANIUM ISOTOPES
YEARS LIVING RADIOISOTOPES
651523* - Nuclear Properties & Reactions
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651525 - Nuclear Properties & Reactions
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