Determination of Phenomenological Optical Model Parameters for Neutrons on ²⁰⁸Pb from 4 to 150 MeV

Author

Randy L. Schutt

Date of Award

12-1986

Degree Name

Master of Arts

Department

Physics

First Advisor

Dr. Robert Shamu

Second Advisor

Dr. Dean Halderson

Third Advisor

Dr. Larry Oppliger

Access Setting

Masters Thesis-Open Access

Abstract

Phenomenological o p tic a l model parameters for neutrons incident on ²⁰⁸Pb have been determined for neutron energies from 4 to 150 MeV using the code SNOOPY-8. Neutron total cross sections from 4 to 150 MeV and angular distributions for elastic scattering from 13.5 to 40.0 MeV were utilized. Analyses of total and differential cross sections were performed at a number of energies to determine energy dependent expressions for the real strengths of the central potential, imaginary surface potential, and imaginary volume potential. These energy dependent expressions for V, W_d, and W_S were found to provide a good fit to the total cross section from 4 to 150 MeV. The energy dependence of the real central potential strength is linear up to about 60 MeV and logarithmic above that energy. The imaginary surface potential strength is approximately parabolic with a peak at about 20 MeV and tends to zero at about 50 MeV. The imaginary volume potential strength, W_S, is zero below 11 MeV, described by a polynominal between 11 and 50 MeV, and linear above 50 MeV.

Recommended Citation

Schutt, Randy L., "Determination of Phenomenological Optical Model Parameters for Neutrons on ²⁰⁸Pb from 4 to 150 MeV" (1986). Masters Theses. 1345.
https://scholarworks.wmich.edu/masters_theses/1345