On the Ionization Yields of Fission Fragments

The disagreement between the distributions in fission fragment mass and ionization is attributed to a variation in ionization yield with fragment mass and to a dispersion arising from such effects as neutron recoil and instrumental errors of ionization measurement. After the effects of dispersion in the available data of fragments from U²³⁵ slow neutron fission are taken into account, the variation in ionization yield is estimated from the remaining disagreement in distributions. For the most probable fission asymmetry, the energy-ionization ratio of light fragments is found to be approximately 3.7 percent less than for heavy fragments.