Does the spherical step‐potential well exhibit the Ramsauer–Townsend effect? Available to Purchase

The ability of the spherical step potential well to model the Ramsauer–Townsend effect, the near disappearance of low‐energy electron scattering in the noble gases argon, krypton, and xenon, is discussed. It is shown that conditions can be found for which the cross section vanishes as the energy approaches zero, but that the noble gas phenomenon, where the cross sections show sharp minima at finite energies, cannot be modeled. The low‐energy s‐wave cross section can be made to vanish, but the p‐wave cross section rises too rapidly with energy to permit a minimum in the total cross section. In addition it is shown that the condition for the vanishing of the s‐wave cross section at zero or low energy also implies the occurrence of a d‐wave resonance at zero or low energy. In the noble gases, the polarization term appears to be the essential feature of the atomic potential which gives rise to the effect.