Giant dipole resonances built on excited nuclear states observed in proton capture and heavy-ion fusion

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5124801

Feldman, G

We have measured {gamma}-ray spectra from the radiative capture reactions {sup 45}Sc(p,{gamma}){sup 46}Ti and {sup 51}V(p,{gamma}){sup 52}Cr over the proton energy range E{sub p} = 4.0-23.5 MeV (E{sub x} {approximately} 14-34 MeV), spanning the giant dipole resonance (GDR) built on excited final states up to E{sub f} {approximately} 10 MeV. Excitation functions for transitions to individual final states or groups of states in {sup 46}Ti and {sup 52}Cr show broad resonances, in addition to a statistical component evident at low {gamma}-ray energy. Inclusive {gamma}-ray spectra from the heavy-ion fusion reactions {sup 19}F + {sup 27}Al and {alpha} + {sup 48}Ti were measured. Angular distributions are nearly symmetric about {theta}{sub {gamma}} = 90{degree} (a{sub 1} {le} 0.1), consistent with a statistical process. Fitted GDR strengths are close to the E1 sum rule, and GDR energies are roughly constant as a function of bombarding energy in each reaction. Resonance widths are broad ({Gamma} {ge} 7 MeV) and increase with bombarding energy. Using the statistical model, we have calculated the compound nucleus contribution to the measured (p,{gamma}) cross section. Measured excitation functions were analyzed by three methods: (1) Lorentzian fits, (2) direct-semidirect calculations and (3) schematic model estimates of integrated GDR strength.

• Research Organization: Washington Univ., Seattle, WA (USA)
• OSTI ID: 5124801
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101 -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ALUMINIUM ISOTOPES
CHARGED PARTICLE DETECTION
CHROMIUM ISOTOPES
DATA
DETECTION
DIPOLE MOMENTS
ENERGY RANGE
EXPERIMENTAL DATA
HEAVY ION FUSION REACTIONS
INFORMATION
ISOTOPES
MEASURING INSTRUMENTS
MEASURING METHODS
MEV RANGE
MEV RANGE 01-10
MEV RANGE 10-100
NUCLEAR REACTIONS
NUMERICAL DATA
PROTON DETECTION
RADIATION DETECTION
SCANDIUM ISOTOPES
TITANIUM ISOTOPES
VANADIUM ISOTOPES