On a problem with strong forward and backward neutron scattering in spheres

The one-speed neutron transport equation with strong forward and backward scattering (characterized by the parameters α and β) may be transformed, according to Image nönü (1973), into an “ordinary” transport equation. However, for spheres this transformation gives an artificial limit for α + β, beyond which it is not useful. In the present work it is shown that numerical results can be obtained in the “forbidden” region by solving the original transport equation by the Sn method, not using the Image nönü transformation.