Beryllium oxide

PHYSICS · Subjective · Fermi University Physics · Nuclear Physics · Nuclear reactions · Fission, fusion and nuclear energy

Energy from Physics, Ch The critical reactor: neutron diffusion, buckling and the size of a core

Problem

Beryllium oxide, considered as a moderator, has a one-group diffusion coefficient

D = 0.60\,\mathrm{cm}

and thermal absorption cross section

\Sigma_a = 4.0\times10^{-4}\,\mathrm{cm^{-1}}

. Compute its thermal neutron diffusion length

L = \sqrt{D/\Sigma_a}