The Scattering of Slow Neutrons by Bound Protons. II. Harmonic Binding—Neutrons of Zero Energy

The cross section for scattering of very slow neutrons by elastically bound protons is calculated by means of the method described in the preceding paper. The results are expressed in terms of a correction factor to be applied to Fermi's factor 4. According to Eq. (5) of the present paper this correction factor is 1+16aJπ1/2 with J defined by Eq. (6) which is suitable for numerical work. The results of numerical calculations for the effects of anisotropy in molecules with axial symmetry are presented in Fig. 1 which has to be used with Eqs. (6.2), (6.3) of the text. For scattering by the H₂O molecule the correction to be applied to Fermi's result is only {~}.3 percent of the final value. Fermi's method is very accurate in this case.