Scattering of electrons by a Coulomb center

New results are obtained from which it follows that systematic use of the one-to-one correspondence between a physical quantity and an operator, which permits the existence of a non-negative quantum distribution function, leads to an "effective" smearing of the potential and to the appearance of a form factor, i.e., to the existence of structure in the scattering center. © 1980 Plenum Publishing Corporation.