THE SLOWING-DOWN OF FISSION NEUTRONS IN BERYLLIUM OXIDE

Technical Report · Thu Jun 01 04:00:00 EDT 1961

OSTI ID:4000040

Goodjohn, A J; Young, J C

The Fermi age to indium resonance for fission neutrons in beryllium oxide was measured. The experiment involved the measurement of the indium- resonance flux along the axis of a rectangular beryllium oxide stack with a plane fission-neutron source placed near one end. The General Atomic linear accelerator was used to provide the primary neutron current by means of the ( gamma ,n) reaction in uranium snd lead and subsequent thermalization in a graphite thermal column. The analysis of the experiment involved the deduction of the infinite second moment from a calculation of the finite moments of the measured distribution. The experimental result was 93.4 cm/sup 2/ with an experimental error of plus or minus 4%. In order to clarify some of the uncertainties associated with the experiment, a calculation of the age was made using a multigroup P/sub 1/ approximation to Boltzmann's equation and the most recent information on fastneutron cross sections and elastic-scattering angular distributions for beryilium and cxygen. The P/sub 1/ result was 91.5 cm/sup 2/ plus or minus 3%. (auth)

• Research Organization: General Atomic Div., General Dynamics Corp., San Diego, Calif.
• NSA Number: NSA-15-026884
• OSTI ID: 4000040
• Report Number(s): GA-1721
• Country of Publication: United States
• Language: English

Related Subjects

BERYLLIUM OXIDES
BOLTZMANN EQUATION
DIFFERENTIAL EQUATIONS
FERMI AGE
FISSION
GAMMA RADIATION
GRAPHITE
GROUP THEORY
INDIUM
LEAD
LINEAR ACCELERATORS
MATHEMATICS
MEASURED VALUES
MODERATORS
NEUTRON FLUX
NEUTRONS
NUCLEAR REACTIONS
NUMERICALS
P1-APPROXIMATION
PHYSICS
RESONANCE
SLOWDOWN
THERMAL COLUMN
TRANSPORT THEORY
URANIUM