SPECTRA OF THE FAST NEUTRONS OF A POLONIUM-BERYLLIUM SOURCE PASSING THROUGH A WATER SHIELD

Journal Article · Sat Feb 01 04:00:00 EST 1964 · At. Energ. (USSR)

OSTI ID:4008536

Doroshenko, G G; Filyushkin, I V

In view of the absence of literature data on the spectra of neutrons emitted by sources based on the ( alpha ,n) reaction after their passage through shielding materials, the effect of passing through water on the fast neutron spectrum of a Po--Be source was experimentally and theoretically investigated. A stilbene fast-neutron spectrometer was used for determining the spectra, measured in a semi-infinite and in barrier-type geometry, using 10, 20, 30, and 40-cm thick water layers. In the latter case, the total neutron flux rate on the detector was 7.7 n/cm/sup 2/ sec for a period of 3 hours. By increasing the thickness of the water layer, the shape of the spectrum was primarily affected by the energy dependence of the total interaction cross section of the neutrons with 0 nuclei. In the case of a semi-infinite medium, the theoretical and experimental values agreed well with each other. The attenuation curve of the source at thicknesses from 0 to 20 cm appeared to be strongly influenced by changes in the nature of the spectrum. (TTT)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-18-021136
• OSTI ID: 4008536
• Journal Information: At. Energ. (USSR), Journal Name: At. Energ. (USSR) Vol. Vol: 16
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

ANISOTROPY
ENERGY
HYDROGEN
MODERATORS
NEUTRONS
NUMERICALS
PHYSICS
SCATTERING
SLOWDOWN
VARIATIONS