Neutron-scattering cross section and analyzing-power measurements for sup 208 Pb from 6 to 10 MeV and optical model analyses

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5907075

Roberts, M L

Differential cross sections and analyzing powers have been obtained for the scattering of neutrons from the ground and first excited states of {sup 208}Pb. These new measurements include differential cross sections for elastic and inelastic neutron scattering at 8.0 MeV, and analyzing powers for elastic and inelastic neutron scattering at 6.0, 7.0, 8.0, 9.0, and 10.0 MeV. The present elastic scattering data have been combined with the previously measured TUNL data and data measured elsewhere in order to obtain a detailed and high accuracy data set for neutron elastic scattering from {sup 208}Pb over the 4.0 to 40.0 MeV energy range. This comprehensive data set has been described using the spherical optical model in which constant geometry fits, energy-dependent geometry fits, and fits incorporating the dispersion relation were performed. Although the overall description of the elastic n+{sup 208}Pb scattering data was reasonably good using the various optical potentials, small systematic discrepancies remained at the backward angles of both the cross section and analyzing power data, and no optical model solution based on conventional Woods-Saxon form factors was found which could describe all of the details seen in the scattering data. To relax the constraint of having a Woods-Saxon form factor, the real central part of the optical model potential was modified using a Fourier-Bessel expansion of the real central potential. Individual fits at 6.0, 7.0, 8.0, 9.0, and 10.0 MeV, and fits to the combined 6.0 to 10.0 MeV data set were obtained using a Fourier-Bessel expansion of the real central potential and compared to fits using a conventional Woods-Saxon form factor.

• Research Organization: Duke Univ., Durham, NC (USA)
• OSTI ID: 5907075
• Country of Publication: United States
• Language: English

Related Subjects

651920* -- Nuclear Properties & Reactions
A=190-219
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANALYZING POWER
BARYON REACTIONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ENERGY LEVELS
ENERGY RANGE
EXCITED STATES
FORM FACTORS
GROUND STATES
HADRON REACTIONS
INELASTIC SCATTERING
LEAD 208 TARGET
MEV RANGE
MEV RANGE 01-10
NEUTRON REACTIONS
NUCLEAR REACTIONS
NUCLEON REACTIONS
OPTICAL MODELS
PARTICLE PROPERTIES
POTENTIALS
SCATTERING
TARGETS