{sup 16}O neutron cross section evaluation
- Lockheed Martin Corp., Schenectady, NY (United States)
This work has resulted from a need to compute more accurately the neutron scattering cross sections and angular distributions for {sup 16}O. Several oxygen evaluations have been performed in the past with R-Matrix theory, including ENDF/B-V and ENDF/B-VI. ENDF/B-VI is an improvement over ENDF/B-V, but still underpredicts in general the forward scattering of neutrons below 2.5 MeV. R-Matrix theory is used in describing cross sections at and near the resonance energies; but may not always be adequate in describing cross sections between resonances, especially when they are widely spaced. The optical (potential well) model of the nucleus is very good in representing cross sections that vary smoothly with energy, but not at describing all of the detailed resonance cross sections. A combination of the potential well model and R-Matrix theory was used for this work to represent cross sections with isolated resonances with large spacings between them. The total neutron cross section of oxygen-16 below 3.0 MeV has widely separated resonances and a dip in the cross section at 2.35 MeV. In the vicinity of resonances, where cross sections vary rapidly with energy, R-Matrix theory has been successful in fitting experimental data. In the region between resonances, an analytical procedure with physical basis is needed that agrees with data over a wide range of energies bracketing regions where experimental measurements are lacking.
- Research Organization:
- Knolls Atomic Power Lab. (KAPL), Niskayuna, NY (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Nuclear Energy, Washington, DC (United States)
- DOE Contract Number:
- AC12-76SN00052
- OSTI ID:
- 307910
- Report Number(s):
- KAPL-P-000091; K-98086; CONF-981003-; ON: DE99001568; TRN: 99:003187
- Resource Relation:
- Conference: International conference on the physics of nuclear science and technology, Long Island, NY (United States), 5-8 Oct 1998; Other Information: PBD: Jun 1998
- Country of Publication:
- United States
- Language:
- English
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