Neutron-electron scattering length and electric polarizability of the neutron derived from cross sections of bismuth and of lead and its isotopes

The electric properties of the neutron have been deduced from precise measurements of coherent scattering lengths and of total cross sections of Pb, of its isotopes with A=208, 207, and 206, and of Bi. Their energy dependences are due to nuclear properties, to nuclear and atomic charges as well as to the neutron’s electric polarizability and to the neutron-electron interaction. We investigated in detail the different evaluations used in the past by German and Russian scientist groups. By means of both data handling methods we found consistent results of ${\mathrm{\alpha }}_{\mathit{n}}$=(0.0±0.5)${10}^{\mathrm{-}3}$ ${\mathrm{fm}}^3$ for the electric polarizability and of ${\mathit{b}}_{\mathit{n}\mathit{e}}$=-(1.32±0.03)${10}^{\mathrm{-}3}$ fm for the neutron-electron scattering length. This result agrees with quark-core models of the neutron.