Optical model for low-energy neutrons on /sup 60/Ni

Journal Article · Fri Feb 01 04:00:00 EST 1985 · Phys. Rev. C; (United States)

DOI:https://doi.org/10.1103/PhysRevC.31.384· OSTI ID:6159540

Winters, R R; Johnson, C H; MacKellar, A D

A previously published s-wave scattering function for 1--450 keV neutrons on /sup 60/Ni is averaged for comparison to the scattering from an optical model potential. The scattering length R' is found to be 5.5 +- 0.03 fm at 225 keV. Averaging of the scattering function (both by integration with a normalized weight function and by use of an analytical approximation) produces shape elastic and compound nucleus cross sections which are then fitted by adjustment of the real and imaginary well depths in both spherical and vibrational optical models with a Woods-Saxon real well (r/sub 0/ = 1.21 fm, a/sub 0/ = 0.66 fm) and a surface derivative imaginary well (r/sub D/ = 1.21 fm, a/sub D/ = 0.48 fm). The fitted depths are V/sub 0/ = 48 MeV and W/sub D/ = 29 MeV for the spherical potentials, and V/sub 0/ = 50 MeV and W/sub D/ = 24 MeV for the vibrational potentials. Uncertainties are +- 5 MeV. From an upper limit on the p-wave strength function the W/sub D/ for p waves is found to be 1.5 MeV for the vibrational model. Thus, the imaginary potential is l dependent for the assumed geometry. For s waves the vibrational model gives a good fit also with W/sub D/ = 1.5 MeV and V/sub 0/ = 54.4 MeV; however, with that V/sub 0/ the 2p states are bound too deeply in /sup 61/Ni and the 3s size resonance is predicted at too low a mass.

• Research Organization: Denison University, Granville, Ohio 43023
• OSTI ID: 6159540
• Journal Information: Phys. Rev. C; (United States), Journal Name: Phys. Rev. C; (United States) Vol. 31:2; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

651615* -- Nuclear Properties & Reactions
A=59-89
Theoretical-- Nuclear Reactions & Scattering-- (-1987)
653007 -- Nuclear Theory-- Nuclear Models-- (-1987)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BARYON REACTIONS
BOUND STATE
COMPOUND-NUCLEUS REACTIONS
CROSS SECTIONS
DIMENSIONS
ELASTIC SCATTERING
ENERGY RANGE
HADRON REACTIONS
KEV RANGE
LENGTH
NEUTRON REACTIONS
NICKEL 60 TARGET
NUCLEAR POTENTIAL
NUCLEAR REACTIONS
NUCLEON REACTIONS
OPTICAL MODELS
P WAVES
PARTIAL WAVES
PHASE SHIFT
POTENTIAL SCATTERING
POTENTIALS
S WAVES
SCATTERING
SCATTERING LENGTHS
TARGETS
WOODS-SAXON POTENTIAL