Evaluation of neutron fundamental parameters from the total cross section data

Using experimental data from the neutron transmission measurements on enriched ^206,207,208Pb, natural Pb and Bi targets, the potential scattering radii R′ and the electric polarizability of the neutron α_n were determined by general least squares fit at fixed neutron-electron bound scattering length values: b_nc = -1.32 · 10^-3 fm (Garching) and b_nc = -1.59 · 10^-3 fm (Dubna). The evaluations were performed in two versions: (1) The potential scattering radii R′ were taken as fitted parameters; (2) R′ values were deduced from optical model calculations. The obtained potential scattering radii values are in the range R′ = 9.0 - 10.0fm. The electric polarizability of the neutron in the first version resulted in α_n = +(0.12 ± 0.44) · 10-³ fm³ with the Garching b_nc value and α_n = -(0.97 ± 0.44) · 10^-3 fm³ with the Dubna b_nc value, but in the second calculation version - in α_n = -(0.14 ± 0.37) · 10^-3 fm³ with both b_nc values. On the basis of obtained results we give preference to the Garching b_nc value.