Systematics of charge distribution studies in low-energy fission of actinides

Charge distribution studies were carried out in the thermal neutron-induced fission of 229Th, 241Pu and 245Cm as well as in the spontaneous fission of 252Cf. The width parameter (σZ /σA), the most probable charge/mass (ZP/AP) and the charge polarization (ΔZ) as a function of fragment mass were deduced. The slope of charge polarization as a function of fragment mass [δ(ΔZ)/δA'], average charge dispersion parameter (left angle σZ right angle) and proton odd-even effect (δP) were also obtained for these fissioning systems. These data along with the literature data for even-Z fissioning systems such as 233Th*, 233U*, 234U*, 236U*, 239U*, 239Pu*, 240Pu* and 250Cf* are discussed in terms of nuclear-structure effects and dynamics of descent from saddle point to the point of neck formation and from the formation of the neck to the scission point. (orig.)