Self shielding in cylindrical fissile sources in the APNea system

Technical Report · Sat Feb 01 00:00:00 EST 1997

DOI:https://doi.org/10.2172/449825· OSTI ID:449825

Hensley, D

In order for a source of fissile material to be useful as a calibration instrument, it is necessary to know not only how much fissile material is in the source but also what the effective fissile content is. Because uranium and plutonium absorb thermal neutrons so Efficiently, material in the center of a sample is shielded from the external thermal flux by the surface layers of the material. Differential dieaway measurements in the APNea System of five different sets of cylindrical fissile sources show the various self shielding effects that are routinely encountered. A method for calculating the self shielding effect is presented and its predictions are compared with the experimental results.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 449825
• Report Number(s): CONF-970126-8; ON: DE97002630; TRN: 97:006444
• Resource Relation: Conference: 5. nondestructive assay/nondestructive examination waste characterization conference, Salt Lake City, UT (United States), 14-16 Jan 1997; Other Information: PBD: [1997]
• Country of Publication: United States
• Language: English

Related Subjects

07 ISOTOPE AND RADIATION SOURCE TECHNOLOGY
66 PHYSICS
THERMAL NEUTRONS
ATTENUATION
FISSILE MATERIALS
SELF-SHIELDING
NEUTRON SOURCES
NEUTRON FLUX
URANIUM 235
PLUTONIUM 239
CROSS SECTIONS
CYLINDRICAL CONFIGURATION
CALIBRATION
RADIOCHEMICAL ANALYSIS
ABSORPTION
MATHEMATICAL MODELS
CALCULATION METHODS
EXPERIMENTAL DATA