Fast-neutron Spectra and Dose-rate Calculations

Journal Article · Sun Jan 01 04:00:00 EST 1961 · Health Physics

DOI:https://doi.org/10.1097/00004032-196105000-00003· OSTI ID:4025545

Eggen, J. B.; French, R. L.; Reetz, A.

A method and its application for calculating fast-neutron spectra and dose rates about the Lid Tank Facility source plate, the Bulk Shielding Reactor, and the Aircraft Shield Test Reactor are described. The method may be applied to any reactor whose shield is composed largely of hydrogenous materials. Dose rates and spectra calculated by the method are useful in shield design and in the analysis of experiments performed in reactor radiation fields. The method is based upon fast-nectron differential energy spectra and dose rates calculated for a point isotropic fission source in infinite media. These data represent a moments method solution of the Boltzmann transport equation for water and hydrocarbons. By representicg a reactor core as an array of point isotropic sources and assuming that any material along the line-of-sight between a point source and a point datector may be represented by an equivalent thickness of water or hydrocarbon, the fastneutron attenuation through any material may be determined by use of the results for these reference materials. The equivalent thickness of non-hydrogenous material is determined from the ratio of the effective removal cross sections. Resuits from dose-rate calcuiations agree with measured BSR and LTSF pure water centerline data within 10%. Calculated and measured spectra for the BSR and tbe ASTR compare favorably, although the AeSTR calculation involves penetration of considerable amounts of nonhydrogenous materials.

• Research Organization: Convair, Fort Worth Tex.
• Sponsoring Organization: USDOE
• NSA Number: NSA-15-024541
• OSTI ID: 4025545
• Journal Information: Health Physics, Journal Name: Health Physics Journal Issue: 3 Vol. 5; ISSN 0017-9078
• Publisher: Health Physics Society
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ABSORPTION
ASTR
BSR-1
CONFIGURATION
CROSS SECTIONS
DIFFERENTIAL EQUATIONS
ENERGY
EQUATIONS
FAST NEUTRONS
HYDROCARBONS
HYDROGEN
LTSF
MEASURED VALUES
RADIATION DOSES
REACTOR CORE
SHIELDING
SHIELDING MATERIALS
SPECTRA
TRANSPORT THEORY
ZONES