Measurement of the Deli,.yed Neutron Fraction and Correction of Small Angle Scattering Data from a Pulsed Spallation Source
نویسندگان
چکیده
The fraction of delayed neutrons in a moderated beam from the enriched uranium, pulsed spallation source at the intense pulsed neutron source at Argonne National Laboratory has been measured and found to be 0.0283 for 450-MeV protons. Delayed neutrons produce a sample-dependent background in time-of-flight instruments . Because of the distribution of neutron wavelengths in the prompt pulse, the significance of the delayed neutron contribution to the observed scattering profile is strongly dependent on the wavelength and therefore on the magnitude of the momentum transfer . This effect is demonstrated, and a general correction procedure in current use for small angle neutron scattering data is described.
منابع مشابه
Small-angle Neutron Scattering from Polymers
III. 1. NUCLEAR FISSION REACTIONS ............................................................................................. 7 III. 2. NUCLEAR REACTORS ............................................................................................................. 7 III. 3. SPALLATION SOURCES ..........................................................................................................
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