NUCLEAR CHARGE DISTRIBUTION IN FISSION

A new prescription has been formulated for calculating the most probable charge Zp associated with a given heavy fragment from the thermal neutron induced fission of 235U. This follows from the observation that a plot of the independent fractional chain yields of the heavy fission fragments against their N Z (neutron to proton ratio), yields a single parabola with the peak at N Z = 1.587±0.005. The independent fractional chain yield data from the thermal-neutron induced fission of 233U and 239Pu and the spontaneous fission of 252Cf conform well to this curve. Available experimental data on Zp in the case of 252Cf are in excellent agreement with the present calculations and are in disagreement with those calculated by the postulates of unchanged charge distribution and maximum energy release. © 1969.