Search for resonance phenomena in /sup 28/Si + /sup 28/Si reactions

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1980

OSTI ID:5265483

DiCenzo, S B

/sup 28/Si + /sup 28/Si reactions have been studied in a search for resonance phenomena similar to those observed in reactions involving lighter nuclei, especially lighter alpha-particle nuclei. Charged particle detection of the evaporation residues at a fixed laboratory angle provides weak evidence for the existence of small (2%) structures in the fusion excitation function. Measurements of the characteristic gamma rays of the evaporation residues reveal 4% structures in the /sup 50/Cr production cross section, consistent with structures of approximately 2% in the total cross section for fusion. The spacing and the magnitude of these structures are shown to be consistent with their arising from successive increments in the value of the maximum angular momentum which leads to fusion. The differential cross section for elastic scattering and for inelastic scattering for Q-values greater than -7 MeV have been measured, at 80/sup 0/ and 90/sup 0/ in the center-of-mass system, for bombarding energies between 70 and 150 MeV. For energies greater than 95 MeV these excitation functions show both broad and narrow structures, similar to the data for lighter identical Boson systems. These data are shown to be consistent with surface transparency in the /sup 28/Si + /sup 28/Si interaction, similar to the situation for the lighter systems. The probable origin of these phenomena in molecule formation, or in orbiting and multiple-step processes, is discussed. The work presented in this thesis constitutes the first study of resonance phenomena in the /sup 28/Si + /sup 28/Si system, and the first in any system consisting exclusively of nuclei heavier than /sup 16/O.

• Research Organization: Yale Univ., New Haven, CT (USA)
• OSTI ID: 5265483
• Country of Publication: United States
• Language: English

Related Subjects

651425* -- Nuclear Properties & Reactions
A=20-38
Experimental-- Nuclear Reactions & Scattering-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CHARGED-PARTICLE REACTIONS
CROSS SECTIONS
DATA
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ENERGY RANGE
EXCITATION FUNCTIONS
EXPERIMENTAL DATA
FUNCTIONS
HEAVY ION REACTIONS
INELASTIC SCATTERING
INFORMATION
MEV RANGE
MEV RANGE 10-100
MEV RANGE 100-1000
NUCLEAR REACTIONS
NUMERICAL DATA
RESONANCE
SCATTERING
SILICON 28 REACTIONS
SILICON 28 TARGET
TARGETS