Production of Low Energy Neutrons by Filtering through Graphite

摘要: Neutrons of energy much lower than thermal were produced by filtering a beam neutrons through block graphite 23 cm long. In such block, Bragg scattering removes the whose wave-length is less largest in graphite, 6.69 angstroms. Measurement boron absorption filtered showed that they had an effective wave-lengh 7.15 angstroms which corresponds to neutron temperatures around 18\ifmmode^\circ\else\textdegree\fi{} Kelvin. The cross section for 0.70\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}24}$ ${\mathrm{cm}}^{2}$. That part this caused incoherence due agitation atoms crystal was demonstrated heating and observing increase section. used show interference effects other substances as Be, Bi, S. water fourfold hydrogen chemical binding observed.